Moved thread: Ron Paul Doesn't Accept Evolution

[Kotatsu]

I did not put the scope only on monkeys

Nor did I put teh scope only on asexual organisms.

Errata:
How can you rule out that they ahve to be significantly different from any organism on Earth?
Corrige:
How can you maintain that they have to be significantly different from any organism on Earth?

I can maintain this in the absence of evidence to the contrary. The probability that this non-Earth life would be significantly similar to Earth life is so small that it is insignificant, barring an unknown mechanism which homogenises life forms across the universe. Drkitten showed you part of the calculation, but we have to add to this, as I pointed out earlier, the necessity of at least a high convergence in exact sequences and evolutionary history for the two sets of life forms to be considered significantly similar. I would propose that there are more zeroes before the first non-zero number in that probability than there are cubic millimetres in the known universe. Therefore, it is safe to assume that non-Earth life forms are overwhelmingly most likely to be significantly different. It is, in fact, a necessity, if no homogenising mechanism exists.

But, in order to say that life on other planets have necessarily to be different from life on Earth, you are making quite some assumptions on:
- "sufficient time will have passed for the organisms on that planet to have evolved beyond the simplest of bacteria",
- "there are Earth-like planets out there", and
- "life is at all possible on planets other than Earth"

How do you propose that I'd be able to discuss at all what life on other planets could be like if I am not allowed to assume that it is at all possible for life to exist on other planets? If I am not allowed this, then the answer to your previous question is patently obvious: life on other planets is by definition and by necessity significantly, not to say fundamentally, different from life on Earth, because that non-Earth life is actually non-life, and thus does not share any characteristics at all with life on Earth, apart from in the sense that they both obey the same chemical and physical laws.

Agreed with that.
So, you can not rule out that they could be similar to organisms on Earth, right?
This is my point.
Why did you disagree?

For the same reason that I cannot rule out that every time I put my foot down, all the electrons and stuff will be aligned in such a way that I will sink to the core of the Earth through the empty space between the nuclei and the electrons. I believe this is called "complete through-fall" or something, and is very unlikely. Unheard of, actually.

I agree with "we can be 100% certain that it is possible for life forms to be constructed in a markedly different manner than Earth life forms."
I disagree with "we can be 100% certain that it is necessary for life forms to be constructed in a markedly different manner than Earth life forms."

If you want to say that:
"we can be 100% certain that it is necessary for life forms to be constructed in a markedly different manner than Earth life forms."
I am asking for evidence

And drkitten gave you a numerical reason why that has to be so, in the absence of evidence of homogenising mechanisms. It even involved a formula. And now you don't want numbers and formulae, bt some othe rkind of evidence?

I believe I have explained why this is a reasonable conclusion above. If you disagree with that explanation, point out where your disagreement is.

Until you can claim that you biologist know exactly how life forms from inanimated matter(*), all you can so is speculate.
I am not willing to place an sure bet on just speculation
(*)know exactly= be able to create a living cat from half a kilo of pure carbon, some other element and water
The cat has to say "mieeow", like all the other cats

You are being ridiculous again. Why would the construction of a cat from inanimate matter at all be relevant to the question of whether or not the genetic code is arbitrary?

We have already discussed the topic extensively.
I may understand that you, as an evolutionary biologist, are pretty attached to some fundamental certainties, and I am not willing to convince you.
I am just expressing your opinion, and I think you got that

Have I managed to convince you that the understanding of the theory of evolution you possessed when you first came to this thread is not the same as the understanding of the theory of evolution espoused by modern science? If not, I am afraid I will not let this go until you put me on ignore^^.

If, at the end of point 4., a living cat(*) come out from the box and bites your nose, I am with you.
(*)the cat has not to be inside the box beforehands
(**) many great scientists died poor

I will perform the experiment multiple times until that happens. Now, please, tell me: have you decided to fund me or not?

[UnrepentantSinner]

Until you can claim that you biologist know exactly how life forms from inanimated matter(*), all you can so is speculate.
I am not willing to place an sure bet on just speculation
(*)know exactly= be able to create a living cat from half a kilo of pure carbon, some other element and water
The cat has to say "mieeow", like all the other cats

I'm going to echo Kotatsu's "rediculous" sentiment. Because you're not asking for evolution here. You're not even asking for abiogenesis. You're asking for spontaneous generation.

[Belz...]

Please, show me the model or the formula where you have that "1 chance out of 1 billion" comes from

I don't think I will. So far you've been unwilling to understand any of the things I've been telling you, so why bother ?

[Belz...]

All this question started from Belz`s comment that life on other planets would be necessarily be different from life on Earth. It is up to him, you, or anybody else to prove the point, not to me to disprove it

And when we explain to you the probabilities, as drkitten did, you ignore it. How convincing.

We do not even know how the biosphere of an hypothetical exo-planet may look like, let alone find one, and we are stating how life there will be like.

But we DO know that some other combinations will be just as functional as those of Earth lifeforms, although we don't find these in Earth life forms...

I fear that there is no such a "passing expert" in the whole scientific community who can answer in detail to the above questions and be able to build some exo-life different from the one specified by me above

http://forums.randi.org/imagehosting/thum_608045fd3d3d0d455.jpg (http://forums.randi.org/vbimghost.php?do=displayimg&imgid=4646)

[Belz...]

I can maintain this in the absence of evidence to the contrary. The probability that this non-Earth life would be significantly similar to Earth life is so small that it is insignificant, barring an unknown mechanism which homogenises life forms across the universe. Drkitten showed you part of the calculation, but we have to add to this, as I pointed out earlier, the necessity of at least a high convergence in exact sequences and evolutionary history for the two sets of life forms to be considered significantly similar. I would propose that there are more zeroes before the first non-zero number in that probability than there are cubic millimetres in the known universe. Therefore, it is safe to assume that non-Earth life forms are overwhelmingly most likely to be significantly different. It is, in fact, a necessity, if no homogenising mechanism exists.

For what it's worth, I was talking mostly in terms of chemical makeup, not morphology. I was only arguing that, if alien lifeforms were found in a stratum, somewhere, we'd be able to tell that they were alien (if we could have a DNA fragment.)

[Kotatsu]

For what it's worth, I was talking mostly in terms of chemical makeup, not morphology. I was only arguing that, if alien lifeforms were found in a stratum, somewhere, we'd be able to tell that they were alien (if we could have a DNA fragment.)

I am with you 100%. Even disregarding morphology and so on, the probabilities are endlessly small. Morphology and sequences and all the rest just add a few zeroes...

[Belz...]

Oh, but they're not 0% ! So how can we possibly say that it's certain ??? :rolleyes:

[volatile]

I'm so late on this theard but I really love the not very smart way of RP supporters trying to defend him. Well i'm a RP supporter myself but the only way to defend him is only by saying that this is a non-issue and has nothing to do with his performance as a president.

If he was a great president and helped the USA would it matter so much that he just was a strong christian so he did not beleive truly in evolution??

Do you not think his disbelief in evolution is indictavie of poor judgement, poor reasoning, dogmatic adherence to nonsense and an unreasonable attitude to science, technology and education? Do you not think that all of those things, particularly poor reasoning and judgement, make someone a rather poor choice to lead a 21st Century superpower?

[Matteo Martini]

I don't think I will. So far you've been unwilling to understand any of the things I've been telling you, so why bother ?

OK, then, let`s stop here.

Do you not think his disbelief in evolution is indictavie of poor judgement, poor reasoning, dogmatic adherence to nonsense and an unreasonable attitude to science, technology and education? Do you not think that all of those things, particularly poor reasoning and judgement, make someone a rather poor choice to lead a 21st Century superpower?

The problem is what you consider the work of the President should be.
I do not think a president should be chosen based on his beliefs on evolution, apparently we have two different visions about what the job of the president has to be.

[Matteo Martini]

I'm going to echo Kotatsu's "rediculous" sentiment. Because you're not asking for evolution here. You're not even asking for abiogenesis. You're asking for spontaneous generation.

About the Kotatsu`s "ridiculous" sentiment, that comment is not directly related to evolution any more, as we have derailed(*) once again talking about if life on Earth has to necessarily be different from life on Earth (this from a comment of Belz, I am trying to remember).
Anyway, I think you should better save your time and not reply to other people`s ridiculous statements at all..
(*) you can consider this as a derail or not

[Matteo Martini]

Nor did I put teh scope only on asexual organisms.


OK then


I can maintain this in the absence of evidence to the contrary.

No way.
If you make a statement, it is up to you to prove the point, not the other way around.
Please, prove me that is is necessary for life on other planets to be different from life on Earth.
Waiting..


The probability that this non-Earth life would be significantly similar to Earth life is so small that it is insignificant, barring an unknown mechanism which homogenises life forms across the universe. Drkitten showed you part of the calculation, but we have to add to this, as I pointed out earlier, the necessity of at least a high convergence in exact sequences and evolutionary history for the two sets of life forms to be considered significantly similar. I would propose that there are more zeroes before the first non-zero number in that probability than there are cubic millimetres in the known universe. Therefore, it is safe to assume that non-Earth life forms are overwhelmingly most likely to be significantly different. It is, in fact, a necessity, if no homogenising mechanism exists.


Show me the (quantitative) model from where this probability come from.
No, the calculation DrKitten has shown is not proving the point, as it takes for granted a lot of things, such as the assumption that each way of mapping codons to amino acids is equally possible in another planet environment.
Evidence?


How do you propose that I'd be able to discuss at all what life on other planets could be like if I am not allowed to assume that it is at all possible for life to exist on other planets?

You can discuss, but you can not state anything for certain.
There is a difference between "discuss" and "state anything for certain"


If I am not allowed this, then the answer to your previous question is patently obvious: life on other planets is by definition and by necessity significantly, not to say fundamentally, different from life on Earth, because that non-Earth life is actually non-life, and thus does not share any characteristics at all with life on Earth, apart from in the sense that they both obey the same chemical and physical laws.


Because you can not state for sure A, it does not mean that you can state for sure B
A=we know how life on other planets should be (i.e.significantly different from life on Earth)
B=non-Earth life is actually non-life


For the same reason that I cannot rule out that every time I put my foot down, all the electrons and stuff will be aligned in such a way that I will sink to the core of the Earth through the empty space between the nuclei and the electrons. I believe this is called "complete through-fall" or something, and is very unlikely. Unheard of, actually.


Certainly, you do not need any model of technical hypothesis to rule out this possibility, do you?


And drkitten gave you a numerical reason why that has to be so, in the absence of evidence of homogenising mechanisms. It even involved a formula. And now you don't want numbers and formulae, bt some othe rkind of evidence?


As DrKitten calculations were perfect, but based on a lot of (unproven) assumptions, such as:
1) each way of mapping codons to amino acids is equally possible
2) we fully know all the mechanisms by which life works
3) we can make hypothesis about the mechanism on natural selection on other planets, and we assume it will not work out as it did on Earth (resulting in monkeys and men)
4) we assume that life can be based on nitrogen and not only carbon (maybe, that was not his assumption, was yours, I am getting confused about all these assumptions)


I believe I have explained why this is a reasonable conclusion above. If you disagree with that explanation, point out where your disagreement is.


I am trying my best


You are being ridiculous again. Why would the construction of a cat from inanimate matter at all be relevant to the question of whether or not the genetic code is arbitrary?


Again with this ridiculous..
How can you claim you perfectly how life works, if you can not create a cat from inanimate matter?
If you do not know how life perfectly works, how can you make 100% certain hypothesis about life should be in planets you know nothing about?


Have I managed to convince you that the understanding of the theory of evolution you possessed when you first came to this thread is not the same as the understanding of the theory of evolution espoused by modern science? If not, I am afraid I will not let this go until you put me on ignore^^.

Unless you do not start insulting me, I have no intention to put you on ignore :D
I have understood that there are various formulation of ToE, the most basic (core) one says that "organisms change".
Then, there are "amendements", like the role of natural selection and genetic drifts.
What are you not exactly willing to let go?


I will perform the experiment multiple times until that happens. Now, please, tell me: have you decided to fund me or not?

How can you prove that the experiment will be a success before the Sun changes into a red giant(*)(**)?
(*)I forgot was this supposed to be the final destiny of our star??..
(**) No assumptions please, I want evidence that you will get the cat living and saying "mieoow" in max 3 months..

[Elizabeth I]

I'm so late on this theard but I really love the not very smart way of RP supporters trying to defend him. Well i'm a RP supporter myself but the only way to defend him is only by saying that this is a non-issue and has nothing to do with his performance as a president.

If he was a great president and helped the USA would it matter so much that he just was a strong christian so he did not beleive truly in evolution??

Why are you talking about politics in a thread about the theory of evolution? Only the thread name remains of the original topic.


Patejdl, go back to the "U.S. Presidential Election" subforum under "Politics" and there is a thread considering this subject from the political viewpoint.

[danielk]

No way.
If you make a statement, it is up to you to prove the point, not the other way around.
Please, prove me that is is necessary for life on other planets to be different from life on Earth.
It is not necessary. But given what we know about the mechanics of life, the probability that it would be identical is so incredibly small that it can simply be ruled out. If you say that we are going to observe exactly the same lifeforms as on earth on another planet -- which by necessity also includes identical environmental conditions -- you are making an extraordinary claim. Yes, it is your claim. It is not reasonable to assume other planets with highly developed life on them are going to be copies of earth.

This is a bit like asking for proof that there is no god. Please.

[Matteo Martini]

It is not necessary. But given what we know about the mechanics of life, the probability that it would be identical is so incredibly small that it can simply be ruled out.

Which, in other words, it is like saying that life on other planets has necessarily to be different from life on Earth (the point I was making)


If you say that we are going to observe exactly the same lifeforms as on earth on another planet -- which by necessity also includes identical environmental conditions -- you are making an extraordinary claim.

Again:
1) I have used the word "exactly", you are using it now
2) I have never made any claim, you (or Kotatsu, or Belz) are the ones who make claims, I do not


Yes, it is your claim. It is not reasonable to assume other planets with highly developed life on them are going to be copies of earth.


When have I claimed that it is reasonable "to assume other planets with highly developed life on them are going to be copies of earth"??
Where did I do that?
At least, unless I have made a major mistake in English

[athon]

Please, prove me that is is necessary for life on other planets to be different from life on Earth.
Waiting..

I'll attempt a stab at this. I've written enough articles on biogenesis to have a fairly good grasp of the field.

First of all, a small point of 'necessity'. I'm not sure who used the word initially, but although it's a pedantic point, it smacks of some form of teleology I'd be happiest avoiding. There's no necessity in life being a particular way - it progresses as it does by way of the rules which govern competition and replication, not because it 'needs' to be that way. (I know, small point, but words have a habit of becoming sticking points in a debate).

First of all we need an essential definition of life which could describe it regardless of its structure or origins. At this point we only have a sample size of one - Earth's. And it is all related to a single system based on imperfectly replicating oligonucleotides assisted by protein structures. Observing this, all life seems to accomplish the following things:

It facilitates the translocation of structures or chemicals (movement)
It generates imperfect copies of its chemistry (reproduction)
It responds to environmental change (senses)
It assimilates chemicals from its immediate environment into its own chemistry (growth and nutrition)
It directly uses energy to change its chemistry (respiration)
It dispels chemicals it no longer has use of (excretes)

The questions that arise are: could non-Earth life exist which would not be observed to subscribe to any of the above? If 'yes', how would we recognise it as life?

So, lets assume the above is the model for any definition of life, as detailed by what we see on Earth. In order to guess at the possible variety of complex chemical systems which could subscribe to these criteria, we'd need to know a few things. One is to speculate on the range of chemistries which could fulfil all of the above, regardless of competition, reaction rates or need for energy (some chemistries would be more efficient than others, naturally, and would outcompete the less efficient ones where overlap for reactants is present). Obviously we don't know the full range, however we can observe on Earth that it is possible for our own system to have less efficient variations. The efficiency of our own replicating chemistry has resulted from it working the best in the pH, salinity, temperature, radiation levels, concentrations etc. of the environment it originally evolved in.

Now, given the variables in this environment which contribute to our own chemistry being so efficient over other contenders (changing any one of which would allow similar chemistries with subtle differences to in turn become more efficient), it is extremely unlikely that we'd find another planet 100% like our own in terms of these variables. Indeed, there is some thought that even on early Earth, a number of environments contained competing proto-biochemistry which, when they overlapped, only those which had developed to a stage of superior fitness could compete effectively for the reactants needed for others to survive. Hence even on a planet nearly identical to Earth's, variations in microenvironments could make all the difference.

So, even though there is close to zero chance xenobiochemistry would be identical to ours, how close could we expect it to be?

It would probably be carbon based, for two reasons: 1) carbon readily forms complex chemistry which requires relatively minimal energy to be manipulated into other forms, 2) other contenders, such as silicon, don't have the same flexibility in bonds and would probably be found in environments where carbon already existed. In other words, carbon chemistry would probably always be in the same environments of its rival chemistries and would outcompete them.

It would probably be aqueous, on account of the nature of water in being more efficient at faciliating chemical reactions.

Beyond that speculation can broaden. Personally, I feel that life forms would probably all reflect certain core features - a core replicating polymer, for instance, which would work in a very similiar way to a nucleotide in many ways. There would be polymeric structures which would assist replication, although not necessarily nitrogenous. There would be cofactors, although again not necessarily of a form we observe here on Earth.

In summary, xenobiochemistry would be recognisable by some features which have analogies on Earth. However, by virtue of variation in environments selecting for the most efficient proto-biochemistries, it is highly unlikely we'd see any system which would be identical to our own.

Athon

[Matteo Martini]

I'll attempt a stab at this. I've written enough articles on biogenesis to have a fairly good grasp of the field.

Good


First of all, a small point of 'necessity'. I'm not sure who used the word initially,

Belz, here:
http://forums.randi.org/showpost.php?p=3283605&postcount=869
it all started long ago..


but although it's a pedantic point, it smacks of some form of teleology I'd be happiest avoiding.

Yes, that is a pedantic point.
Sorry for being rude


There's no necessity in life being a particular way - it progresses as it does by way of the rules which govern competition and replication, not because it 'needs' to be that way. (I know, small point, but words have a habit of becoming sticking points in a debate).


Please, define what you mean by "particular way".
You can give many meanings to that word


First of all we need an essential definition of life which could describe it regardless of its structure or origins. At this point we only have a sample size of one - Earth's. And it is all related to a single system based on imperfectly replicating oligonucleotides assisted by protein structures. Observing this, all life seems to accomplish the following things:

[..]

I read it all, and I can agree with you, as you certainly know much more than me on the subject.
I would just like to point out that yours are, so far, only assumptions.
Informed assumptions, but assumptions.
This, as we have no sample of exo-life, so far


It would probably be carbon based, for two reasons: 1) carbon readily forms complex chemistry which requires relatively minimal energy to be manipulated into other forms, 2) other contenders, such as silicon, don't have the same flexibility in bonds and would probably be found in environments where carbon already existed. In other words, carbon chemistry would probably always be in the same environments of its rival chemistries and would outcompete them.


I see that, even when you speak about life being based on carbon, you write "probably".
Good
As we have no evidence that life can not, somehow, be based on iron :)
No proof


It would probably be aqueous, on account of the nature of water in being more efficient at faciliating chemical reactions.


Again, "probably".
I agree.
Maybe, we can have life forms living on methane-based environments, who knows..


Beyond that speculation can broaden. Personally, I feel that life forms would probably all reflect certain core features - a core replicating polymer, for instance, which would work in a very similiar way to a nucleotide in many ways. There would be polymeric structures which would assist replication, although not necessarily nitrogenous. There would be cofactors, although again not necessarily of a form we observe here on Earth.


Good
I start to like you.
You use the word "speculation" as you bear in mind we are now only speculating.


In summary, xenobiochemistry would be recognisable by some features which have analogies on Earth. However, by virtue of variation in environments selecting for the most efficient proto-biochemistries, it is highly unlikely we'd see any system which would be identical to our own.


Ah..
Two problems here:
1) you have forgotten that you have used the words "speculation", "probably", so far, and you start making predictions about how life on other planets has to be.
"Highly unlikely".
Can you give me a percentage for that?
1 possibility out of 1 million?
1 possibility out of 1 billion?
from which model this number comes from?

2) It would be quite difficult to have a system on another planet which is "identical" to the system on Earth, if not from the fact that you can not find on Earth two organisms, even of the same species, which are "identical"

[danielk]

I see that, even when you speak about life being based on carbon, you write "probably".
Good
As we have no evidence that life can not, somehow, be based on iron :)
No proof
Dude, you do realize this undermines your own position? Also, science doesn't deal with proofs.

[Matteo Martini]

Dude, you do realize this undermines your own position? Also, science doesn't deal with proofs.

Daniel,
I do not know how to tell you that I am not claiming anything.
Other people claim.
I am just questioning other people`s claims
ADD
Proof=evidence
SECOND ADD
Just to avoid confusion, the claim I am challenging is this:
http://forums.randi.org/showpost.php?p=3283605&postcount=869

[athon]

Please, define what you mean by "particular way". You can give many meanings to that word

As in 'the way life appears to be on Earth'.

I read it all, and I can agree with you, as you certainly know much more than me on the subject.
I would just like to point out that yours are, so far, only assumptions.
Informed assumptions, but assumptions.
This, as we have no sample of exo-life, so far

As I said, it's based on a sample size of one. However, the significant point is that if we came across a phenomena on another planet, what observations would we have which would lead us to describing it as 'life'? If they didn't subscribe to the definition we've reduced terrestrial life to, why would we still call it life? Don't forget, some of the features I proposed are intrinsically linked, as well. It would be impossible to have metabolism without energy changes, for instance.

I see that, even when you speak about life being based on carbon, you write "probably".
Good. As we have no evidence that life can not, somehow, be based on iron :)
No proof

Proof, no. Evidence...yes.

Life, at its core, depends on complicated material interactions. While we have no extraterrestrial living systems to investigate, we do have non-biological reactions using other elements which could point out what sort of chemistry could lend itself to following the criteria I pointed out above. It is unlikely that iron, for example, could form the same role carbon does in a chemical system which has the features we'd recognize as living.

Again, "probably".
I agree.
Maybe, we can have life forms living on methane-based environments, who knows..

We could, if methane was cold enough to be liquid. Gaseous environments, while fluid (hence open to efficient chemical reactions) could possibly have very slow complex chemistry, and it has been postulated that very rudimentary biochemistry could take place in a gaseous medium. I hold my reservations on that, however, for a few reasons.

Good
I start to like you.
You use the word "speculation" as you bear in mind we are now only speculating.

Speculation is free. It starts to cost when one invests more than the imagination in them, though. :)

Ah..
Two problems here:
1) you have forgotten that you have used the words "speculation", "probably", so far, and you start making predictions about how life on other planets has to be.

It's not a 'probably' in this case as the definition by which we'd identify life would need to be by virtue of what we know of here, at least initially. You'd be free to speculate on life which does not reflect the above postulations, but the evidence is stacked heavily against anything we'd identify as life being removed from having such features.

"Highly unlikely".
Can you give me a percentage for that?
1 possibility out of 1 million?
1 possibility out of 1 billion?
from which model this number comes from?

Sorry, it's not a prediction I have solid figures on, especially without knowing enough about the variety of extraterrestrial planets which allow for complex chemistry. Perhaps somebody else might offer the chance of coming across another planet which is 100% identical to our own. So far, of the several hundred planets we do have some data on, Earth seems pretty unique.

2) It would be quite difficult to have a system on another planet which is "identical" to the system on Earth, if not forn the fact that you can not find on Earth two organisms, even of the same species, which are "identical"

We're not talking about morphology here, don't forget, but rather variations in basic biochemistry.

Athon

[UnrepentantSinner]

About the Kotatsu`s "ridiculous" sentiment, that comment is not directly related to evolution any more, as we have derailed(*) once again talking about if life on Earth has to necessarily be different from life on Earth (this from a comment of Belz, I am trying to remember).
Anyway, I think you should better save your time and not reply to other people`s ridiculous statements at all..
(*) you can consider this as a derail or not

Thanks for the advice, but given the hours of manlife you alone have wasted with your obfuscations, handwaving, tangents and straw men, I don't see why my couple of minutes echoing a sentiment noting how rediculous your straw man request for evidence is, is consequential in the least.

I've wasted more time waiting for busses than I have reading your posts to this thread.

But, to quote you, anyway, how about answering my comment about how you're demanding Spontaneous Generation as evidence of evolution rather than just grousing about one f-ing word in my reply to you?

[Belz...]

Please, prove me that is is necessary for life on other planets to be different from life on Earth.
Waiting..

What do you mean 'waiting' ? You've been answered by more than one poster, more than once. What do you want, exactly ?

[Kotatsu]

The problem is what you consider the work of the President should be.
I do not think a president should be chosen based on his beliefs on evolution, apparently we have two different visions about what the job of the president has to be.

We don't have presidents here (yet), so maybe I'm wrong, but wouldn't it be much better to, before deciding who to vote for, survey every candidate's stance towards following reason and/or following emotion? If we find that one candidate is prepared to accept objective and scientific facts, even if he personally dislike what these facts imply, while the other candidate more easily is swayed by preconceived notions on how he believes the facts should be, and disregard or dismiss any and all evidence to the contrary, then is this not a good measure of how the two candidates are likely to react in another situation where facts are pitted against myth?

Would you rather have a president who accepts that planes crashed into the World Trade Centre, leading to a cascade effect which caused their destruction and the death of thousands, or one which is fully prepared to believe that elves caused this out of spite, because this is what a source with no information on the subject leads him to believe?

But why am I continuing the political discussion?

[ArmillarySphere]

I think the probability of finding even a single organism that is sufficiently identical to an Earth-based one to be essentially impossible to distinguish from among a group of them is on the order of 1 out of 10 to the power of millions, if not billions. I might as well stop ruling out the possibility that I will suddenly quantum tunnel to the Earth's core. I think that one is actually higher...

[Kotatsu]

No way.
If you make a statement, it is up to you to prove the point, not the other way around.
Please, prove me that is is necessary for life on other planets to be different from life on Earth.
Waiting..

Okey. I believe I have already done this, but:
The evidence in favour of assuming that non-Earth life forms will necessarily be different from Earth life forms, both fundamentally (i.e. in chemical
composition) and on a more shallow level (i.e. morphologically, and so on] can be summed up in the following set of non-numerical arguments. The reason these arguments are non-numerical is that, as drkitten has showed, the numbers quickly get too large for them to have any meaning to us; we cannot relate to that kind of numbers, and thus the discussion of exact odds, while certainly possible to make, are more or less irrelevant. That said:

We know that the morphology and physiology of modern taxa is the result not only of the conditions they live under today, but also of the conditions they have lived under in earlier times. We know that evolution uses what exists at the moment, and does not plan ahead. These two general statements suggest that the morphology and physiology of modern taxa is entirely dependent on that of the earlier taxa from which they are derived. For instance, there is the classical example of the panda's thumb, which is analogous, not homologous, to that of other Carnivora.

So even if non-Earth life is the same on the molecular level, it is highly unlikely that it will be the same on the macroscopic level. However:

We further know that these principles hold true also on the molecular level: reaction paths, cascade systems, and simple and complex protein ultrastructures are the result of a continuous evolution of these systems throughout evolutionary time. As we have seen more and more often over the last few years, structures hitherto assumed or believed to be what a certain sect of naive people refer to as "irreducibly complex" are, in fact, the result of past combinations of structures which, originally, often were used for a different purpose, but which, through well known processes, have been co-opted into more advanced structures.

So even if non-Earth life uses the same coding system for their proteins and stuff, there is no reason to assume that the same structures will have evolved even on the cellular level. However:

We know, on an even lower level, that the DNA code we teach kids at school is only one of many. To my knowledge, there are at least ten different working codes which are used in different kinds of genes in different groups of organisms. While the majority of the codons are probably the same on Earth (I have only ever used two of the settings, and have never studied this in particular, however), there are also several differences. I mentioned as an example the fact that what is coded as one of the amino acids in the standard code is coded as a stop codon in the invertebrate mitochondrial code, which means that differences between the codes can be quite fundamental. The exact code used seems to be arbitrary, with the similarity between the Earth codes being a result of common descent. A small subset of the possible combinations are used by Earth organisms, but if non-Earth organisms at all use DNA as their coding system for inheritance, there appears to be no reason they should chose the exact same system as we use here. It's not even the same system throughout Earth life!

This suggests that even if they use DNA like we do, it is unlikely that the translation from DNA to product will be the same; However:

We can go even deeper into fundamentals. We know that the bases we use in the coding of DNA are not the only ones which work. RNA, for instance, uses a slightly different set of bases. Occasionally, aberrant bases occur in both DNA and RNA, even though these are usually selected away in the next generation (which, in turn, can lead to mutations).

This means that the even if we assume that they use the same kinds of molecules in their composition as we do, there is no need for these to the exact same molecules. However:

While a less likely scenario than the other, there is a chance that non-Earth life will be composed of compounds primarily based on other elements than hydrogen, carbon, nitrogen and oxygen, as most of the "life molecules" on Earth are. Silicon based life has been mentioned, and there may be other plausible ways to construct it, especially if the planet they live on is significantly different from Earth.

This is, in essence, what we know, and the conclusions we can draw from it. While this certainly does not prove that life on other planets necessarily is different from Earth life, it makes the odds against similarity on all levels so staggeringly astronomical, that it is not only possible, but rather necessary to disregard the possibility that they are similar.

I see Athon has made a splendid effort to explain this from a slightly different angle. Apart from applauding his explanation, I can only urge you, Matteo, to reread it, as well as my contribution, and point out where you disagree with us.

No, the calculation DrKitten has shown is not proving the point, as it takes for granted a lot of things, such as the assumption that each way of mapping codons to amino acids is equally possible in another planet environment.
Evidence?

The very idea that different planetary circumstances would result in slightly or fundamentally different codings is evidence in support of our contention. If we don't even have a consistent code system across the Earth flora and fauna, which has, after all, evolved under the same planetary circumstances, why should a biota of extraterrestrial origin evolved under different circumstances necessarily develop the same code?

You can discuss, but you can not state anything for certain.
There is a difference between "discuss" and "state anything for certain"
Because you can not state for sure A, it does not mean that you can state for sure B
A=we know how life on other planets should be (i.e.significantly different from life on Earth)
B=non-Earth life is actually non-life

No. If I am not allowed to assume that life is possible on planets other than Earth, I cannot discuss or even speculate what life on other planets would be like, because there wouldn't be anything to discuss. It would, in essence, be the following conversation:

Me: Well, I suppose life on other planets cou---
You: There is no life on other planets!

Discussion over.

Certainly, you do not need any model of technical hypothesis to rule out this possibility, do you?

Why not? The possibility is on the same scale as that non-Earth life will be identical to Earth life.

As DrKitten calculations were perfect, but based on a lot of (unproven) assumptions, such as:
1) each way of mapping codons to amino acids is equally possible
2) we fully know all the mechanisms by which life works
3) we can make hypothesis about the mechanism on natural selection on other planets, and we assume it will not work out as it did on Earth (resulting in monkeys and men)
4) we assume that life can be based on nitrogen and not only carbon (maybe, that was not his assumption, was yours, I am getting confused about all these assumptions)

You are wrong in 2, 3, and 4. These assumptions are not necessary for drkitten's calculation. Assumption 1 is only necessary to a certain degree. There are a large number of theoretically possible codes, but, limiting ourselves to the supposition that non-Earth life will at least vaguely follow the same evolutionary laws as Earth life, we can rule out the great majority of these from the start.

The redundancy of the genetic code is based on the need for a certain amount of mutations being allowable. But the majority of the mutations should not result in too drastic changes, as this is likely to kill off the individual before reproduction. Therefore, the third position in a codon is often irrelevant to the resulting amino acid: XXA, XXC, XXG, and XXT code for the same amino acid. We can therefore focus primarily on that subset of all possible combinations which has this feature, as they are the ones most likely to be useful in the long run.

This is still a very large amount, though.

Again with this ridiculous..
How can you claim you perfectly how life works, if you can not create a cat from inanimate matter?
If you do not know how life perfectly works, how can you make 100% certain hypothesis about life should be in planets you know nothing about?

This is an engineer's view of the world, it is not universally applicable. I could, given time, learn exactly what every base in the human genome does, and what every protein does, and so on. I would still not be able to build a human. How would I do it? By simply pouring the necessary elements in to a bucket, stir it for half an hour, and pour it into a man-shaped mould? The practicalities are insurmountable, even if the theory is well known. It would not only take a perfect knowledge of the matter, it would also take perfect control of every atom used at every given moment, and the ability to form the correct molecules exactly at the correct time in the correct place. Perhaps one day that will be possible, but it certainly isn't today.

However, this does in no way forbid us from coming up with hypotheses about what life could be like. I can say with 100% certainty that the qualities I have listed over and over again (sensory organs, a mode of reproduction, mobility, autotrophy, heterotrphy, a gastrointestinal tract in larger organisms, a mechanism for inheritance of information, and so on) are likely to occur also in non-Earth life.

Perhaps there are planets which do not give organisms the opportunity to use sensory equipment, and thus these are never evolved. Perhaps other planets do not give the opportunity for organisms to evolve mobility. But I would like to see what kind of life could evolve without any of these characteristics. I echo Athon's question when I ask what kind of entity we could call life which has no characteristics of life; no reproduction, no intake and expenditure of energy, no mobility?

I am not sure what a "100% certain hypothesis" is, though.

How can you prove that the experiment will be a success before the Sun changes into a red giant(*)(**)?
(*)I forgot was this supposed to be the final destiny of our star??..
(**) No assumptions please, I want evidence that you will get the cat living and saying "mieoow" in max 3 months..

Then you are changing the premises of the experiment. I will not discuss this further if you continue to add requirements once the already established ones are met.

[Kotatsu]

I read it all, and I can agree with you, as you certainly know much more than me on the subject.
I would just like to point out that yours are, so far, only assumptions.
Informed assumptions, but assumptions.
This, as we have no sample of exo-life, so far

What are you after, really? We all agree that we have no examples of non-Earth life so far, but the discussion is about what it would be like, and if it would have to differ from Earth life, should we find non-Earth life. This by definition means we will have to speculate based on what we know from the only system of life we are currently aware of: that of Earth.

If we are not allowed to use the mechanisms and constructs we know work in a discussion on how else it could work, there is really only one conclusion that can be made: there are an infinite amount of possible ways in which life can be constructed. If we do not limit ourselves to the subset contained by those possibilities which involve the known ways for life to work, the suspected ways for life to work, and the theoretically plausible ways for life to work, we can say nothing at all. And if that is so, what is the point of this discussion at all?

I mean, you have already forbidden me to assume that life can exist on other planets than Earth...

[Matteo Martini]

As in 'the way life appears to be on Earth'.


OK, I beg to make you notice that this is not really a simple statement, as you can not say that a bacteria is the same as a whale.
So, we have to find some common denominator to all life on Earth (being based on C, for example)


As I said, it's based on a sample size of one. However, the significant point is that if we came across a phenomena on another planet, what observations would we have which would lead us to describing it as 'life'? If they didn't subscribe to the definition we've reduced terrestrial life to, why would we still call it life? Don't forget, some of the features I proposed are intrinsically linked, as well. It would be impossible to have metabolism without energy changes, for instance.


I admit that is another point which complicates the matter
How do you define "life"?
AFAIK, there is no "straightforward" definition of "life"


Proof, no. Evidence...yes.

Life, at its core, depends on complicated material interactions. While we have no extraterrestrial living systems to investigate, we do have non-biological reactions using other elements which could point out what sort of chemistry could lend itself to following the criteria I pointed out above. It is unlikely that iron, for example, could form the same role carbon does in a chemical system which has the features we'd recognize as living.


AFAIK, you can not prove (=proof) that life can not be based on other elements than carbon



We could, if methane was cold enough to be liquid.

Like in Neptune?


Gaseous environments, while fluid (hence open to efficient chemical reactions) could possibly have very slow complex chemistry, and it has been postulated that very rudimentary biochemistry could take place in a gaseous medium. I hold my reservations on that, however, for a few reasons.


I remember that I have read one (few?) article(s) speculating on life in lake of methane.
Anyway, that was speculation


Speculation is free. It starts to cost when one invests more than the imagination in them, though. :)


I agree.
We have to remember that we are speculating here


It's not a 'probably' in this case as the definition by which we'd identify life would need to be by virtue of what we know of here, at least initially. You'd be free to speculate on life which does not reflect the above postulations, but the evidence is stacked heavily against anything we'd identify as life being removed from having such features.


What "evidence" are you talking about?


Sorry, it's not a prediction I have solid figures on, especially without knowing enough about the variety of extraterrestrial planets which allow for complex chemistry.

Then, as long as you do not call it a "prediction", I agree


Perhaps somebody else might offer the chance of coming across another planet which is 100% identical to our own. So far, of the several hundred planets we do have some data on, Earth seems pretty unique.

One reason more not to claim we can know how life would be on exo-planets for sure

[Matteo Martini]

We don't have presidents here (yet), so maybe I'm wrong, but wouldn't it be much better to, before deciding who to vote for, survey every candidate's stance towards following reason and/or following emotion?

The problem is not that simple.
Just to give you an example, Communists were obsessed with logic and reason in sociology and reason, and they claimed their vision of economy was based on sound science.
Too bad Communist economy failed grandly


If we find that one candidate is prepared to accept objective and scientific facts, even if he personally dislike what these facts imply, while the other candidate more easily is swayed by preconceived notions on how he believes the facts should be, and disregard or dismiss any and all evidence to the contrary, then is this not a good measure of how the two candidates are likely to react in another situation where facts are pitted against myth?


It depends what role you should think the President should have.
If you consider him/her as a "employee" that has to keep spending on line and promote free market, maybe it is not that important which views he/she holds on evolution(*)
It is a question of priorities
(*)I do not endorse RP`s comments on evolution


Would you rather have a president who accepts that planes crashed into the World Trade Centre, leading to a cascade effect which caused their destruction and the death of thousands, or one which is fully prepared to believe that elves caused this out of spite, because this is what a source with no information on the subject leads him to believe?


Come ooooooooooooooonnnnnn!!
Kotatsu, now you are really derailing here, and using the wrong example.
RP has never aknowledged any conspiracy theory about 911.
Now, I have to ask you another question.
Would you prefer a president who has voted for the Iraqi invasion(*), as Hillary Clinton, or a president who had the guts to vote against, as Ron Paul?
What is more important, world peace or belief on evolution?
(*)x00000 civilian deaths so far
But why am I continuing the political discussion?[/QUOTE]

[danielk]

Matteo, you do realize that we can establish an upper bound of probability, only from what we know about how life works on earth? Anything beyond that is definitely going to lower the probability even further that extraterrestrial life will be similar to life on earth.

[Matteo Martini]

What are you after, really? We all agree that we have no examples of non-Earth life so far, but the discussion is about what it would be like, and if it would have to differ from Earth life, should we find non-Earth life. This by definition means we will have to speculate based on what we know from the only system of life we are currently aware of: that of Earth.


I am after nothing.
This is the problem.
I have the suspect that I am heavily contested here as many people asssume I am of a creationist in disguise, and no statement from my side can take away this opinion.
I have read a statement from Belz.. who says that life on other planets has to necessarily be different from Earth.
I do not agree with this statement, as I do not think we can make any absolute statement about how life on other planets is, just informed, well-thought assumptions.
On the assumptions people have made, I mostly agree, for the little I know


If we are not allowed to use the mechanisms and constructs we know work in a discussion on how else it could work, there is really only one conclusion that can be made: there are an infinite amount of possible ways in which life can be constructed. If we do not limit ourselves to the subset contained by those possibilities which involve the known ways for life to work, the suspected ways for life to work, and the theoretically plausible ways for life to work, we can say nothing at all. And if that is so, what is the point of this discussion at all?


We can say a lot of things.
We can speculate.


I mean, you have already forbidden me to assume that life can exist on other planets than Earth...

Where on Earth did I forbid you to do so?
Where?

[Matteo Martini]

Matteo, you do realize that we can establish an upper bound of probability, only from what we know about how life works on earth? Anything beyond that is definitely going to lower the probability even further that extraterrestrial life will be similar to life on earth.

No, I do not realize that for the following reasons:
1) any value about upper bounds in probability has to come out from a statistical model built to describe the subject on which you want to get the upper bound of probability;
2) the statistical model has to describe wholly the subject it means to describe, in this case, how life is formed, how statistically exo-planets environments are and how good they are to host life, how possible and how life can happen to be generated in exo-planets, how life can evolve there, ..
3) we, at the moment, do not have a model detailed enough to describe what is in number 2)
4) we can not make statistical predictions you are talking about

[Matteo Martini]

I think the probability of finding even a single organism that is sufficiently identical to an Earth-based one to be essentially impossible to distinguish from among a group of them is on the order of 1 out of 10 to the power of millions, if not billions. I might as well stop ruling out the possibility that I will suddenly quantum tunnel to the Earth's core. I think that one is actually higher...

Evidence?

[danielk]

No, I do not realize that for the following reasons:
1) any value about upper bounds in probability has to come out from a statistical model built to describe the subject on which you want to get the upper bound of probability;
Agreed.

2) the statistical model has to describe wholly the subject it means to describe, in this case, how life is formed, how statistically exo-planets environments are and how good they are to host life, how possible and how life can happen to be generated in exo-planets, how life can evolve there, ..
No. Let's just assume they will be all identical to Earth in environmental conditions. Anything less than identity would only lower the probability of identical life, thus it's the correct assumption for establishing an upper bound.

3) we, at the moment, do not have a model detailed enough to describe what is in number 2)
We do, let's just take Earth itself.

4) we can not make statistical predictions you are talking about
You are wrong about this, too, as has been shown to you by people who are well-versed in the study of biology on this planet.

I think this verbal argument actually proves that, for the purposes of calculating an upper bound of probability, any hypothesized extraterrestrial planet can simply be equated with Earth.

q.e.d.?

[athon]

OK, I beg to make you notice that this is not really a simple statement, as you can not say that a bacteria is the same as a whale.
So, we have to find some common denominator to all life on Earth (being based on C, for example)

We're not talking about morphology, but rather biochemistry. And biochemically whales and bacteria both subscribe to the same, related system, with only variations in form and interaction.

I admit that is another point which complicates the matter
How do you define "life"?
AFAIK, there is no "straightforward" definition of "life"

Nature isn't very helpful with classifications. It's a human thing. It's why categories and definitions are useless outside of contexts. People try hard to cram life into a dichotomy of 'biotic' and 'abiotic'...where nature doesn't seem to comply.

AFAIK, you can not prove (=proof) that life can not be based on other elements than carbon

'Proof' is a mathematical term. Science goes by weight of evidence.

What "evidence" are you talking about?

Life on this planet subscribes to the criteria I cited.

Then, as long as you do not call it a "prediction", I agree

Why do predictions need to have defined figures? Science is full of educated guesses which form predictions without solid quantities. You seem to have picked a silly way of being convinced of a notion. Feel free, but meanwhile science moves on without you.

One reason more not to claim we can know how life would be on exo-planets for sure

I'm not sure of your point. The possibility of life on another planet having the exact same biochemistry as our own is vanishingly tiny. The reasoning behind this has been shown. Science never works on certainties, but some ideas can be ignored until we have reason to consider them. One such idea that can be ignored until we have reason to look at it is that of xenobiochemistry being identical to our own.

Again, feel free to continue to focus on the fact that we can't be certain...but science works on reservation of evidence. Until such evidence is presented, we're free to speculate, but it amounts to little more than fantasising and intellectual masturbation, ultimately.

Athon

[Matteo Martini]

We're not talking about morphology, but rather biochemistry. And biochemically whales and bacteria both subscribe to the same, related system, with only variations in form and interaction.


It would be better for you to tell exactly what in the biochemistry of bacteria and whales you think it would necessarily be not-present in other planets` life systems


Nature isn't very helpful with classifications. It's a human thing. It's why categories and definitions are useless outside of contexts. People try hard to cram life into a dichotomy of 'biotic' and 'abiotic'...where nature doesn't seem to comply.


Agreed.
This is why it is even more difficult to say what life in other plaets should be, as we do not have really a one-way definition of "life" itself


'Proof' is a mathematical term. Science goes by weight of evidence.


I used the terms "proof" and "evidence" interchangeably, maybe a mistake of my English


Life on this planet subscribes to the criteria I cited.


So, you use life in this planet as evidence about how life on other planets should be?
Without not one example of exo-planet life system?


Why do predictions need to have defined figures? Science is full of educated guesses which form predictions without solid quantities. You seem to have picked a silly way of being convinced of a notion. Feel free, but meanwhile science moves on without you.


Ah..
When people start to not know how to reply, they start to use words as "ridicule" and "funny".
I claim you can not make about how life on other planets can be unless you have a pool of examples (of other planets` systems).
Now, the example pool is as big as 1 life system (Earth`s).
This is not enough to make solid predictions whatsoever.
Statistically


I'm not sure of your point. The possibility of life on another planet having the exact same biochemistry as our own is vanishingly tiny.

Evidence?


The reasoning behind this has been shown.

A lot of reasoning has been shown, but no evidence.
If you throw a coin once, and you get 52% tail and 48% head, you can start making predictions about how many head and tails you get if you throw the coin other 40 times
If you throw the coin only once, and you get "head", you can not make predictions about the next 100 times you throw the coin.


Science never works on certainties, but some ideas can be ignored until we have reason to consider them. One such idea that can be ignored until we have reason to look at it is that of xenobiochemistry being identical to our own.


It is the other way around.
I have never claimed that "xenobiochemistry being identical to our own".
Other people have claimed that it is necessarily different.
I have asked for evidence for that.
Not assumptions, evidence


Again, feel free to continue to focus on the fact that we can't be certain...but science works on reservation of evidence. Until such evidence is presented, we're free to speculate, but it amounts to little more than fantasising and intellectual masturbation, ultimately.

Athon

This is exactly my point.
Until there is evidence that xenobiochemistry being different to our own, all we can do is what you call "little more than fantasising and intellectual masturbation"

[Matteo Martini]

Agreed.


No. Let's just assume they will be all identical to Earth in environmental conditions. Anything less than identity would only lower the probability of identical life, thus it's the correct assumption for establishing an upper bound.


Why do you have to assume that "they will be all identical to Earth in environmental conditions"??
Where does this assumption come from, as it has little do to with what we are talking?????


We do, let's just take Earth itself.


Earth is not a "model"
Earth is a planet
I have asked for a model.
Not for a planet


You are wrong about this, too, as has been shown to you by people who are well-versed in the study of biology on this planet.


I like the fact that, when people have problems to reply to a point, they resort to call the opponent`s argument "silly" or they resort to the fact that people talking here are "well-versed"..


I think this verbal argument actually proves that, for the purposes of calculating an upper bound of probability, any hypothesized extraterrestrial planet can simply be equated with Earth.

q.e.d.?

No.
What would prove the argument is have 1000 exoplanet life systems ( a sample of our galaxy, if not of all the Universe) studied, and find that they are all based on another element other than Carbon.
This is what I call "evidence"

[Complexity]

Any person who doesn't accept that the theory of evolution has an extraordinary amount of evidence supporting it is unworthy of any public office and is not someone who I would care to know.

Ron Paul is a fool. He wasn't a good libertarian (I, on the other hand, am) and has sunk so low as to run as a Republican.

Ron Paul prefers superstition to science. What a contemptible little man.

[Complexity]

Matteo Martini - Please stop using the word 'proof'. You don't understand what it means.

[Matteo Martini]

Okey. I believe I have already done this, but:
The evidence in favour of assuming that non-Earth life forms will necessarily be different from Earth life forms, both fundamentally (i.e. in chemical
composition) and on a more shallow level (i.e. morphologically, and so on] can be summed up in the following set of non-numerical arguments. The reason these arguments are non-numerical is that, as drkitten has showed, the numbers quickly get too large for them to have any meaning to us;

I do not really understand what you mean by "The reason these arguments are non-numerical" is because number gets too large, anywayI was pointing out that the numbers shown by DrKitten take for granted many assumptions:
1) each way of mapping codons to amino acids is equally possible
2) we fully know all the mechanisms by which life works
3) we can make hypothesis about the mechanism on natural selection on other planets, and we assume it will not work out as it did on Earth (resulting in monkeys and men)
4) we assume that life can be based on nitrogen and not only carbon (maybe, that was not his assumption, was yours, I am getting confused about all these assumptions)
..


we cannot relate to that kind of numbers, and thus the discussion of exact odds, while certainly possible to make, are more or less irrelevant. That said:

We know that the morphology and physiology of modern taxa is the result not only of the conditions they live under today, but also of the conditions they have lived under in earlier times. We know that evolution uses what exists at the moment, and does not plan ahead. These two general statements suggest that the morphology and physiology of modern taxa is entirely dependent on that of the earlier taxa from which they are derived. For instance, there is the classical example of the panda's thumb, which is analogous, not homologous, to that of other Carnivora.


Now you are speaking about evolution on Earth, which we know


So even if non-Earth life is the same on the molecular level, it is highly unlikely that it will be the same on the macroscopic level.

Now, you are making assumptions about evolution on other planets, which we do not know


However:

We further know that these principles hold true also on the molecular level: reaction paths, cascade systems, and simple and complex protein ultrastructures are the result of a continuous evolution of these systems throughout evolutionary time. As we have seen more and more often over the last few years, structures hitherto assumed or believed to be what a certain sect of naive people refer to as "irreducibly complex" are, in fact, the result of past combinations of structures which, originally, often were used for a different purpose, but which, through well known processes, have been co-opted into more advanced structures.

So even if non-Earth life uses the same coding system for their proteins and stuff, there is no reason to assume that the same structures will have evolved even on the cellular level.

And no reason to assume which different structure will have evolved
So, no assumptions should be done


However:

We know, on an even lower level, that the DNA code we teach kids at school is only one of many. To my knowledge, there are at least ten different working codes which are used in different kinds of genes in different groups of organisms. While the majority of the codons are probably the same on Earth (I have only ever used two of the settings, and have never studied this in particular, however), there are also several differences. I mentioned as an example the fact that what is coded as one of the amino acids in the standard code is coded as a stop codon in the invertebrate mitochondrial code, which means that differences between the codes can be quite fundamental. The exact code used seems to be arbitrary, with the similarity between the Earth codes being a result of common descent. A small subset of the possible combinations are used by Earth organisms, but if non-Earth organisms at all use DNA as their coding system for inheritance, there appears to be no reason they should chose the exact same system as we use here. It's not even the same system throughout Earth life!

Now, you are using the right word!!
Congratulations!!
The word has been bolded by me in your quoted text.
"appears"


This suggests that even if they use DNA like we do, it is unlikely that the translation from DNA to product will be the same; However:

We can go even deeper into fundamentals. We know that the bases we use in the coding of DNA are not the only ones which work. RNA, for instance, uses a slightly different set of bases. Occasionally, aberrant bases occur in both DNA and RNA, even though these are usually selected away in the next generation (which, in turn, can lead to mutations).

This means that the even if we assume that they use the same kinds of molecules in their composition as we do, there is no need for these to the exact same molecules.

Again.
I congratulate again.
Right word used again.
I have bolded it again in your quoted text.


However:

While a less likely scenario than the other, there is a chance that non-Earth life will be composed of compounds primarily based on other elements than hydrogen, carbon, nitrogen and oxygen, as most of the "life molecules" on Earth are. Silicon based life has been mentioned, and there may be other plausible ways to construct it, especially if the planet they live on is significantly different from Earth.


I have to say that I keep agreeing with you more and more.
There are other "plausible" ways to construct it.
There is a chance.
Good.


This is, in essence, what we know, and the conclusions we can draw from it. While this certainly does not prove that life on other planets necessarily is different from Earth life, it makes the odds against similarity on all levels so staggeringly astronomical, that it is not only possible,

No.
Now you are being wrong again..
;(
You are moving into making claims on things you have no evidence about.
Where is the "staggeringly astronomical" come from?
Again, do you have a model for that?


I see Athon has made a splendid effort to explain this from a slightly different angle. Apart from applauding his explanation, I can only urge you, Matteo, to reread it, as well as my contribution, and point out where you disagree with us.


I am trying my best.
Even if it is taking me a lot of time to do that.


The very idea that different planetary circumstances would result in slightly or fundamentally different codings is evidence in support of our contention. If we don't even have a consistent code system across the Earth flora and fauna, which has, after all, evolved under the same planetary circumstances, why should a biota of extraterrestrial origin evolved under different circumstances necessarily develop the same code?


I have never claimed that "a biota of extraterrestrial origin evolved under different circumstances necessarily develop the same code"
I have made no claims
Other people did


No. If I am not allowed to assume that life is possible on planets other than Earth, I cannot discuss or even speculate what life on other planets would be like, because there wouldn't be anything to discuss. It would, in essence, be the following conversation:

Me: Well, I suppose life on other planets cou---
You: There is no life on other planets!


Wrong
Now, I have really to write in bold underlined.
You are putting in my mouth claims I have never made.
I have made no claims.
Other people (you included) did


You are wrong in 2, 3, and 4. These assumptions are not necessary for drkitten's calculation. Assumption 1 is only necessary to a certain degree. There are a large number of theoretically possible codes, but, limiting ourselves to the supposition that non-Earth life will at least vaguely follow the same evolutionary laws as Earth life, we can rule out the great majority of these from the start.


The assumptions are needed.
If you want to make accurate predictions, you have to base them into evidence (my points 2,3 and 4)


[..]This is an engineer's view of the world, it is not universally applicable. I could, given time, learn exactly what every base in the human genome does, and what every protein does, and so on. I would still not be able to build a human. How would I do it? By simply pouring the necessary elements in to a bucket, stir it for half an hour, and pour it into a man-shaped mould? The practicalities are insurmountable, even if the theory is well known. .

If the theory is well know, you can at least build a model out of it and be able to make quantitative predictions.
Not impossible in theory.
Is there any model to describe life?


It would not only take a perfect knowledge of the matter, it would also take perfect control of every atom used at every given moment, and the ability to form the correct molecules exactly at the correct time in the correct place. Perhaps one day that will be possible, but it certainly isn't today.

Not even one day, proabbly.
You can do it statistically.
This is know we can build calculators and chips.
Using statistical tools.


However, this does in no way forbid us from coming up with hypotheses about what life could be like. I can say with 100% certainty that the qualities I have listed over and over again (sensory organs, a mode of reproduction, mobility, autotrophy, heterotrphy, a gastrointestinal tract in larger organisms, a mechanism for inheritance of information, and so on) are likely to occur also in non-Earth life.


This is not a quantitative model


Perhaps there are planets which do not give organisms the opportunity to use sensory equipment, and thus these are never evolved. Perhaps other planets do not give the opportunity for organisms to evolve mobility. But I would like to see what kind of life could evolve without any of these characteristics. I echo Athon's question when I ask what kind of entity we could call life which has no characteristics of life; no reproduction, no intake and expenditure of energy, no mobility?
[..]
Then you are changing the premises of the experiment. I will not discuss this further if you continue to add requirements once the already established ones are met.

You have claimed that you will repeat the experiment over and over.
Can I ask you to finish the experiment in 30 years, or is it a too short time?
40 years?

[athon]

It would be better for you to tell exactly what in the biochemistry of bacteria and whales you think it would necessarily be not-present in other planets` life systems

I don't understand what you're saying. Could you rephrase, please?

So, you use life in this planet as evidence about how life on other planets should be?
Without not one example of exo-planet life system?I think I've perhaps found a sticking point here.

'Life' has a definition, thus far. It is open to modification only on observing phenomena which could warrant a revision.

If we observe a phenomena on an extraterrestrial body which reminds us of the criteria I posited, we'd need to discuss whether it was close enough to what we'd define as 'life' to warrant a revision.

For instance, if we saw something that didn't reproduce, didn't change energy, and didn't grow...why would we view it as 'alive'? You might say 'but we haven't looked', but it doesn't matter. It would be like suggesting it possible that asteroids exist which are made totally out of sugar. Sure, we've not visited a substantially large number of asteroids...but going on chemistry we have access to here on Earth, we can be confident in saying sugary asteroids don't exist.

In short, based not so much of what we know just of living processes but of chemistry as well (of which life is just a complicated chemical process), we can make certain predictions of the nature of xenobiology with extremely high confidence.

Ah..
When people start to not know how to reply, they start to use words as "ridicule" and "funny".
I claim you can not make about how life on other planets can be unless you have a pool of examples (of other planets` systems).You are wrong. Plain and simple. You've been shown why. We can use chemistry and current definitions of life to make such predictions.

I know you're insinuating that the definitions for life could change. In my honest opinion, I predict that on finding something totally different to our current definition would warrant less a revision of that definition, and more a complication and diversification of biology. We'd find new ways to describe it, and 'life' would give way to a richer range of words and descriptions. In my opinion, it will become oversimplistic - indeed, even wrong - to say of such a phenomena 'it's a life form on that planet' even though many might crave such simplicity.

Right now we have only one definition of life, and a relatively simple category of biology resulting from it. We are free to suggest it could become complicated on finding proto-biochemistry or chemistry with life-like behaviour. But we are confident in being correct to assume that life as the word currently is defined will not be identical in chemistry elsewhere in the universe as it is on Earth, forgiving, of course, a situation where our own biological history arose elsewhere. We base that purely on life being complicated, replicating chemical systems.

If you wish to discuss whether there is a phenomena which could be observed, with view of physics and chemistry as we currently understand it, which has features sufficient to warrant us describing it as 'alive', then you'd need to speculate on how this might be possible.

I anticipate you might well say 'we wouldn't know until we saw it', but this argument could be used for anything, such as speculating that there could be a giant pink bunny hiding on the other side of Pluto. We wouldn't know until we saw it, afterall...

You can see, therefore, where your argument becomes 'silly' if that were the case.

Athon

[Matteo Martini]

It would be like suggesting it possible that asteroids exist which are made totally out of sugar. Sure, we've not visited a substantially large number of asteroids...but going on chemistry we have access to here on Earth, we can be confident in saying sugary asteroids don't exist.


The point, is that it is you who are making claims such as "it possible that asteroids exist which are made totally out of sugar".
Not me. I will reply to the other points later

EDIT
What is the definition of "life"?

[athon]

The point, is that it is you who are making claims such as "it possible that asteroids exist which are made totally out of sugar".

Wrong. It is us saying 'based on what we understand of chemistry and asteroids we have access to, they cannot be made of sugar'. You then state that because we have never seen asteroids elsewhere, that we can't make such claims.

What is the definition of "life"?

Are you serious? After all this? Are you reading any of these posts?

Look, I'll make this really, really simple. We'll start with this question and take it further if you can give an answer: how would we recognise something as 'alive' if it did not match the definition we'd proposed based on current observations?

Athon

[Matteo Martini]

Wrong. It is us saying 'based on what we understand of chemistry and asteroids we have access to, they cannot be made of sugar'. You then state that because we have never seen asteroids elsewhere, that we can't make such claims.


We know a lot more about composition of asteroids than about how life is generated from matter
We have seen lots of asteroids around, but only one life system (Earth`s)


Are you serious? After all this? Are you reading any of these posts?

Look, I'll make this really, really simple. We'll start with this question and take it further if you can give an answer: how would we recognise something as 'alive' if it did not match the definition we'd proposed based on current observations?

Athon

Please, give me a definition of "life"

[Kotatsu]

The problem is not that simple.
Just to give you an example, Communists were obsessed with logic and reason in sociology and reason, and they claimed their vision of economy was based on sound science.
Too bad Communist economy failed grandly

The problem is exactly that simple. If a candidate is prepared to throw out facts and reason for myth in one case which, admittedly, is not essential to the running of his country, why shall I assume he will not do the same at a more crucial juncture? By dismissing evolution --- one of the most well-founded scientific theories we have --- he is, in effect, saying that the scientific process and method needs not necessarily yield a truth with which he is more comfortable than the shepherd's bedtime stories he was told as a kid. Just as how I would not care to live under a ruler who saw Winnie the Pooh or Little Nemo's Adventures in Slumberland as truth and dogma, and thereby discard by default all evidence to the contrary, I would not want a creationist as my ruler. It is exactly as simple as that.

It depends what role you should think the President should have.
If you consider him/her as a "employee" that has to keep spending on line and promote free market, maybe it is not that important which views he/she holds on evolution(*)
It is a question of priorities
(*)I do not endorse RP`s comments on evolution

I would see him as the foremost --- of the "first among equals" variety --- of a vast body of elected or otherwise selected capable civil servants whose job it is to carry out the wishes of the electoral body for the continuing stability and survival of the community (which does not necessarily consist of the nation state, a concept I despise). In this capacity, I would rather expect him to be the figurehead for the process, than some kind of absolute ruler, and I would certainly expect him to favour objective facts and scientific conclusions in any field before the whims of those of faith.

Come ooooooooooooooonnnnnn!!
Kotatsu, now you are really derailing here, and using the wrong example.

Yes. So let us leave the politics out of this. My political views are basically of a nature I have often seen ridiculed or used as a derogatory term on this forum, and I do not care to drag them into this debate either. This will thus likely be my last political post in this thread.

RP has never aknowledged any conspiracy theory about 911.

It was an analogy. Sort of like an example.

Now, I have to ask you another question.
Would you prefer a president who has voted for the Iraqi invasion(*), as Hillary Clinton, or a president who had the guts to vote against, as Ron Paul?
What is more important, world peace or belief on evolution?

As the two concepts are in no way the opposites of each other, I would say that both are of equal importance, with the exception that there is no such thing as "belief in evolution".

If those were the only two options, and the candidates were equal in all other respects, I would have voted for Ron Paul as well, but as I understand it, all other things are not equal, and basing such an important decision on one aspect of their proposed politics alone is silly, as other aspects of their political beliefs could very well weigh up a belief that war is the best solution to a particular situation.

[Kotatsu]

Where on Earth did I forbid you to do so?
Where?

I will admit this was a bit of a rhetorical hyperbole, based on your dislike of assumptions and want to get rid of them in the discussion, combined with:

"These are not assumptions. The assumptions involved are: "sufficient time will have passed for the organisms on that planet to have evolved beyond the simplest of bacteria", "there are Earth-like planets out there", and "life is at all possible on planets other than Earth". However, if we don't make these assumptions, there is no point in discussing this at all." (Post 987)

[Kotatsu]

I do not really understand what you mean by "The reason these arguments are non-numerical" is because number gets too large, anywayI was pointing out that the numbers shown by DrKitten take for granted many assumptions:
1) each way of mapping codons to amino acids is equally possible
2) we fully know all the mechanisms by which life works
3) we can make hypothesis about the mechanism on natural selection on other planets, and we assume it will not work out as it did on Earth (resulting in monkeys and men)
4) we assume that life can be based on nitrogen and not only carbon (maybe, that was not his assumption, was yours, I am getting confused about all these assumptions)

I have explained why this assessment is wrong before. drkitten's calculation does not assume 2, 3, and 4, and only assumes 1 to a certain extent, as the argument certainly works, though with slightly reduced efficacy, when the mitigating circumstances I outlines above are taken into consideration.

By the way, that drkitten's calculations assume these 4 things is a claim for which I hereby submit that I will require evidence if you are to repeat them.


Now you are speaking about evolution on Earth, which we know
Now, you are making assumptions about evolution on other planets, which we do not know
And no reason to assume which different structure will have evolved
So, no assumptions should be done
Now, you are using the right word!!
Congratulations!!
The word has been bolded by me in your quoted text.
"appears"
Again.
I congratulate again.
Right word used again.
I have bolded it again in your quoted text.
I have to say that I keep agreeing with you more and more.
There are other "plausible" ways to construct it.
There is a chance.
Good.
No.
Now you are being wrong again..
;(
You are moving into making claims on things you have no evidence about.
Where is the "staggeringly astronomical" come from?
Again, do you have a model for that?

It is apparent that you either didn't read this carefully, or didn't understand it. It is a systematic reduction of the concept of "similarity" to its gradually smaller parts. Essentially, it is an explanation for why similarity to Earth life is unlikely. Of course that would involve taking examples from Earth life, as that is what is being compared.

In many of the cases you have asserted that I make unfounded assumptions, none are made, or the assumption is based on the discussion before it. The first section, for instance, explains how the morphology of modern taxa is a result of ancestral taxa and the environment they evolved in. For this to be replicated on another planet several highly unlikely things would have to happen. First of all, not only must the conditions have been the same here as there in recent times, but it would have to be the same -- at least on the macroscopic level --- throughout the evolutionary history of both planets.

Of course there could be a planet where something that looks exactly like a subset of the Earth fauna has evolved. I am not denying this possibility. I am just explaining that the possibility is infinitesimally small. And a large part of this is because all organs of all organisms on such a planet would be analogous, not homologous, barring a sympanspermic event.

I am making claims, yes, but I believe I put some reasoning behind it in an attempt to show that these are well-founded assumptions. We have evidence of ways that actually work, and we have evidence of ways that work, but are not used, and we have evidence of ways that probably work, and those that plausibly work, and those that possibly work. We're not making this up as we go along for the sake of contrariness, you know!

Wrong
Now, I have really to write in bold underlined.
You are putting in my mouth claims I have never made.
I have made no claims.
Other people (you included) did

But you did criticise my assumptions. One of the assumptions you criticised was "life on other planets is at all possible". Thus my reaction, because to criticise this assumption is ludicrous in a discussion of what life on other planets could be like.

Again, that was an example, not a direct quote. After this post, I will write all examples and analogies in a different colour, so the confusion will be lessened.

The assumptions are needed.
If you want to make accurate predictions, you have to base them into evidence (my points 2,3 and 4)

You have made this claim, now. Provide evidence that drkitten's calculation cannot be arrived at without the assumption of points 2-4.

Not even one day, proabbly.
You can do it statistically.
This is know we can build calculators and chips.
Using statistical tools.

Yes. We can build incredibly simple things. This does not extrapolate into building incredibly complex things. We can build a sand castle on the beach, but we can't build a working ecosystem on the planetary level.

This is not a quantitative model

The devil take quantitative models! Screw them! In complex systems like biological science, they are worthless, pointless and useless. Quantitative models are one tiny subset of all possible and permissible models in science. They are used only in the simple sciences where variables and constants are countable, and needed only in those fields where numbers are believed to have the ability to smooth over the feelings of insecurity in the scientist before the gaze of the unloving universe. I am quite fed up with this insistence that only numbers, formulae, and quantitative models count. That is a skewered, perverted, and above all fundamentally WRONG way to look at the world!!! WAKE UP!!!

You have claimed that you will repeat the experiment over and over.
Can I ask you to finish the experiment in 30 years, or is it a too short time?
40 years?

The experiment would of course be finished the very minute a life form occurs in the box. This is similar to how the testing of the hypothesis "following the logic of the theory of evolution and its amendments, we will never find the fossils of a rabbit in a pre-cambrian stratum" is also a test that will continue for ever.

[athon]

Please, give me a definition of "life"

It's been done. The fact you've even asked means you're not following, Matteo, either because you can't, you won't, or are pretending because you feel maintaining this position gives you some sort of pseudo-intellectual gameplay. I'm not sure which.

Nonetheless, I'll give the benefit of the doubt (based on the fact you're demonstrating a weak understanding of biology as it is) that you've just missed the general definition:

Life is an interaction of complex chemistry which complies to the following criteria:

It facilitates the translocation of structures or chemicals (movement)
It generates imperfect copies of its chemistry (reproduction)
It responds to environmental change (senses)
It assimilates chemicals from its immediate environment into its own chemistry (growth and nutrition)
It directly uses energy to change its chemistry (respiration)
It dispels chemicals it no longer has use of (excretes)

Now, are you going to answer my question or not?

Athon

[Belz...]

It would be better for you to tell exactly what in the biochemistry of bacteria and whales you think it would necessarily be not-present in other planets` life systems

:rolleyes: You're just being willfully obtuse, Matteo. It's already been explained to you how numerous the equivalent possibilities are.

[Belz...]

The devil take quantitative models!

No, I don't think I will.

[Kotatsu]

No, I don't think I will.

Picky eater?

[Kotatsu]

Just for the record, these are the 14 genetic codes which can be selected in EditSeq:

Standard Genetic Code
Ciliate Macronuclear
Echinodermate Mito
Invertebrate Mito
Mold Mito & Mycoplasma
Plant Mito
Protozoan Mito
Vertebrate Mito
Yeast Mito
Best E. coli Rev Trans
Degen. E. coli Rev Trans
Mammalian Rev Trans
Worst E.coli Rev Trans
Yeast Rev Trans

Mito is, of course short for mitochondria. However, I have no idea what differs between these codes, and as I have never studied E. coli, I don't know what the difference between Best, Degen[erate] and Worst is. However, even disregarding the E. coli translations by lumping them together in one, that still leaves 11 genetic codes which are well-enough known and widely used to be included in a commercial program like EditSeq. There may very well be others we don't know of. For instance, I have heard that Cnidarians and Ctenophorids behave strangely. They are the only groups in which the COI gene is not a useful barcoding gene, for instace (according to Hebert and his group). Maybe they are likely candidates for another code?

[Belz...]

Picky eater?

Allergies.

[Matteo Martini]

Life is an interaction of complex chemistry which complies to the following criteria:


The nuclear reactions in the Sun are also "interaction of complex chemistry".
Is the Sun living?


It facilitates the translocation of structures or chemicals (movement)


So does any truck..


It generates imperfect copies of its chemistry (reproduction)


So, a Catholic priest is not living, as he can not reproduce.
The notion of "imperfect" is not clear, you mean "inexact"?


It responds to environmental change (senses)


So do automatic doors in every shop


It assimilates chemicals from its immediate environment into its own chemistry (growth and nutrition)


Toilet paper, if you throw it over a pond of water, "assimilates chemicals from its immediate environment into its own chemistry", where chemicals=H2O, the toilet paper becomes wet


It directly uses energy to change its chemistry (respiration)


So do any rechargeable battery, during the recharge process


It dispels chemicals it no longer has use of (excretes)


So does my car (chemicals=discharge gas)


Now, are you going to answer my question or not?


Please, come out with a better definition of life

It's been done. The fact you've even asked means you're not following, Matteo, either because you can't, you won't, or are pretending because you feel maintaining this position gives you some sort of pseudo-intellectual gameplay. I'm not sure which.

Instead of accusing me to not follow you or to engage in any kind of gameplay, if you think this is the case, I invite you not to reply to this discussion anymore.
I am already using much of my valuable time to reply in this thread.

[athon]

The nuclear reactions in the Sun are also "interaction of comlex chemistry".
Is the Sun living?

Does it subscribe to all of the criteria?

So does any truck..


Does it subscribe to all of the criteria?

So, a Catholic priest is not living, as he can not reproduce.

Huh? You're really playing silly games now.

The notion of "imperfect" is not clear, you mean "inexact"?

Semantics. You know what I mean (then again...maybe I am giving you too much credit there).

So do automatic doors in every shop

Does it subscribe to all of the criteria?

Toilet paper, if you throw it over a pond of water, "assimilates chemicals from its immediate environment into its own chemistry", where chemicals=H2O, the toilet paper becomes wet

I am now convinced you're playing games, Matteo. Either that, or your comprehension of chemistry is below that of my younger students. Which is pretty sad.

So do any rechargeable battery, during the recharge process

Does it subscribe to all of the criteria?

So does my car (chemicals=discharge gas)

Does it subscribe to all of the criteria?

Please, come out with a better definition of life

Why? You clearly can't comprehend the one I've put forward. Maybe if you had a grasp of biology and chemistry beyond primarily school level...

And no, I'm not intentionally trying to insult you. Your above responses seriously show you're just not up to understanding what has been put forward.

Instead of accusing me to not follow you or to engage in any kind of gameplay, if you think this is the case, I invite you not to reply to this discussion anymore.
I am already using much of my valuable time to reply in this thread.

Ah, I guess if you're time is so valuable, you probably shouldn't be wasting it trying to learn things which are a little beyond you. Either that or invest in some foundational text books. If you're going to ask questions about this topic it might pay to know a little more about what you're asking.

Athon

[Matteo Martini]

The problem is exactly that simple. If a candidate is prepared to throw out facts and reason for myth in one case which, admittedly, is not essential to the running of his country, why shall I assume he will not do the same at a more crucial juncture? By dismissing evolution --- one of the most well-founded scientific theories we have --- he is, in effect, saying that the scientific process and method needs not necessarily yield a truth with which he is more comfortable than the shepherd's bedtime stories he was told as a kid. Just as how I would not care to live under a ruler who saw Winnie the Pooh or Little Nemo's Adventures in Slumberland as truth and dogma, and thereby discard by default all evidence to the contrary, I would not want a creationist as my ruler. It is exactly as simple as that.

1) your notion of "ruler" is somehow unclear, if you see the "ruler" as a King, the President should not be anyone`s King
2) there are many criteria to choose a President, for many people, me included, endorsement in evolution (call it as you wish) is not the most important
3) is RP a creationist?


I would see him as the foremost --- of the "first among equals" variety --- of a vast body of elected or otherwise selected capable civil servants whose job it is to carry out the wishes of the electoral body for the continuing stability and survival of the community (which does not necessarily consist of the nation state, a concept I despise). In this capacity, I would rather expect him to be the figurehead for the process, than some kind of absolute ruler, and I would certainly expect him to favour objective facts and scientific conclusions in any field before the whims of those of faith.

As I said, I think there are many other criteria to choose the President, and you will hardly find one that matches 100% your beliefs.
I am strongly against gun liberalization, for example, while RP is strongly in favour.
Just an example..


Yes. So let us leave the politics out of this. My political views are basically of a nature I have often seen ridiculed or used as a derogatory term on this forum, and I do not care to drag them into this debate either. This will thus likely be my last political post in this thread.


OK


It was an analogy. Sort of like an example.


Mm..
You have also implied that he is a creationist, when you said "I would not want a creationist as my ruler".
I do not think that RP has endorsed creationism


As the two concepts are in no way the opposites of each other, I would say that both are of equal importance, with the exception that there is no such thing as "belief in evolution".


Call it as you wish:
"endorsement of evolution"?
My point is that you can hardly find a candidate that matches 100% your positions.
You have to make choices


If those were the only two options, and the candidates were equal in all other respects, I would have voted for Ron Paul as well, but as I understand it, all other things are not equal, and basing such an important decision on one aspect of their proposed politics alone is silly, as other aspects of their political beliefs could very well weigh up a belief that war is the best solution to a particular situation.

In my personal opinion, have a President not endorsing evolution is a cheap price to pay to have a President who is strongly anti-war

I will admit this was a bit of a rhetorical hyperbole, based on your dislike of assumptions and want to get rid of them in the discussion, combined with:
[..]

OK, I have to ask you to stick as possible to what I say as you can.
In order not to have further confusion on this thread

[Matteo Martini]

Huh? You're really playing silly games now.


You wrote:
"It [living organism] generates imperfect copies of its chemistry (reproduction) "
That was one of your criteria to define if something is living or not.
I have given you the example of the Catholic priest.
He can not reproduce.
So, as from your points, he is not living.
I will tell my pastor, as soon as I meet him.
So?

[Paulhoff]

The nuclear reactions in the Sun are also "interaction of complex chemistry".
Is the Sun living?
The nuclear reactions of the Sun have nothing to do with any form of chemistry, complex and/or otherwise.

Paul

:) :) :)

That is why it is called nuclear power, not chemical power.

[Matteo Martini]

I have explained why this assessment is wrong before. drkitten's calculation does not assume 2, 3, and 4, and only assumes 1 to a certain extent, as the argument certainly works, though with slightly reduced efficacy, when the mitigating circumstances I outlines above are taken into consideration.

By the way, that drkitten's calculations assume these 4 things is a claim for which I hereby submit that I will require evidence if you are to repeat them.


I do repeat them.
DrK assumed, for example, that all the ways of mapping codons to amino acids are exactly equally probable to be found in life systems


It is apparent that you either didn't read this carefully, or didn't understand it. It is a systematic reduction of the concept of "similarity" to its gradually smaller parts. Essentially, it is an explanation for why similarity to Earth life is unlikely. Of course that would involve taking examples from Earth life, as that is what is being compared.

Or it is you who does not understand.
The explanation is very well done, but it is based on words, not evidence


In many of the cases you have asserted that I make unfounded assumptions, none are made, or the assumption is based on the discussion before it. The first section, for instance, explains how the morphology of modern taxa is a result of ancestral taxa and the environment they evolved in. For this to be replicated on another planet several highly unlikely things would have to happen. First of all, not only must the conditions have been the same here as there in recent times, but it would have to be the same -- at least on the macroscopic level --- throughout the evolutionary history of both planets.


How can you rule out that life is impossible at all, if the conditions are not the same, and if they are not the same "throughout the evolutionary history of both planets"?
I would like to see evidence(*), not assumptions(**)
(*)evidence=one example of exo-life where life has happened with the evolutionary history of the exo-planet being different from Earth`s
(**)Dr Kitten`s formulae


Of course there could be a planet where something that looks exactly like a subset of the Earth fauna has evolved. I am not denying this possibility. I am just explaining that the possibility is infinitesimally small.

How much small?
1 out of 1 million?
1 out of 1 billion?
Where does the number comes from?
Where is the model, where are the formulae?
No, DrKitten calculation does not work for that, as I said above


And a large part of this is because all organs of all organisms on such a planet would be analogous, not homologous, barring a sympanspermic event.

I am making claims, yes, but I believe I put some reasoning behind it in an attempt to show that these are well-founded assumptions.

Well-founded or not, these are and remain as "assumptions", not "evidence".


We have evidence of ways that actually work, and we have evidence of ways that work, but are not used, and we have evidence of ways that probably work, and those that plausibly work, and those that possibly work. We're not making this up as we go along for the sake of contrariness, you know!

We have evidence only of one example of life system, that is Earth`s, so we should not make claims about other life systems, as a pool of one example is not enough to make good predictions of a group of other life systems (provided that they exist, in first place)
Every person who has done statistics, even basic level, should not that you can not draw any conclusion out of a pool of one example


But you did criticise my assumptions. One of the assumptions you criticised was "life on other planets is at all possible". Thus my reaction, because to criticise this assumption is ludicrous in a discussion of what life on other planets could be like.

Criticizing your assumptions =! Stating the opposite of your assumptions.
If I criticize you as you say "black", in no way means I am saying "White"


Again, that was an example, not a direct quote. After this post, I will write all examples and analogies in a different colour, so the confusion will be lessened.

I think this could be a good idea :D


You have made this claim, now. Provide evidence that drkitten's calculation cannot be arrived at without the assumption of points 2-4.


As, for example, Dr Kitten`s calculations take for granted that all the ways of mapping codons to amino acids are exactly equally probable to be found in life systems.
http://forums.randi.org/showpost.php?p=3304045&postcount=970
I would like to see evidence for that.


Yes. We can build incredibly simple things. This does not extrapolate into building incredibly complex things. We can build a sand castle on the beach, but we can't build a working ecosystem on the planetary level.


This is one of the reasons why it is very hard to prove how life in other planets should or should not be (basically, my point).


The devil take quantitative models! Screw them! In complex systems like biological science, they are worthless, pointless and useless. Quantitative models are one tiny subset of all possible and permissible models in science. They are used only in the simple sciences where variables and constants are countable, and needed only in those fields where numbers are believed to have the ability to smooth over the feelings of insecurity in the scientist before the gaze of the unloving universe. I am quite fed up with this insistence that only numbers(*), formulae, and quantitative models count. That is a skewered, perverted, and above all fundamentally WRONG way to look at the world!!! WAKE UP!!!


Bold mine.
Is that a rant or what?
Was not DrKitten who wrote numbers?
I think I did not write many numbers here, others did.
I quote him:
"That's 1 chance in 100,000,000,000,000,000,000,000,000,000,000,000,00 0,000,000,000,000,000,000,000,000,000,000,000,000, 000,000,000,000,000,000,000,000,000,000,000,000."
I am just asking for evidence for that number ( for example, the proof that all the ways of mapping codons to amino acids are exactly equally probable to be found in life systems, something that DrK and you and maybe others are taking for granted).
If you do not like numbers, bring me other evidence, like some alien forms, all different from Earth`s life forms, the report of all the exo-planets you have visited, which should be a good sample of the planets of all the solar systems in the galaxy, just bring some evidence..


The experiment would of course be finished the very minute a life form occurs in the box.

If you want to obtain a financing for your experiment, as you asked, you have to write a timeline by which the experiment will be over (no, writing "the experiment would of course be finished the very minute a life form occurs in the box" will not work, sorry)


This is similar to how the testing of the hypothesis "following the logic of the theory of evolution and its amendments, we will never find the fossils of a rabbit in a pre-cambrian stratum" is also a test that will continue for ever.

This is why I also wrote a timeline for that, if you remember.

[Matteo Martini]

The nuclear reactions of the Sun have nothing to do with any form of chemistry, complex and/or otherwise.

Paul

:) :) :)

That is why it is called nuclear power, not chemical power.

According to the Chemistry Department of Duke University, there is something called "Nuclear Chemistry"
"Without this energy from the sun, life could not exist as we know it. Without nuclear chemistry the sun would not exist."
More here: http://www.chem.duke.edu/~jds/cruise_chem/nuclear/nuclear.html
You do not like the example?
Googling..
Dynamic Ice: Surface Physics Technique Reveals Complex Chemical Reactions on Icy Surfaces and Atmospheric Ice Crystals
http://gtresearchnews.gatech.edu/newsrelease/esd.htm
Ice crystals (non-living things) also involve "Complex Chemical Reactions".

EDIT - ADD
We were talking about "interaction of complex chemistry", not "chemical power"

[Paulhoff]

According to the Chemistry Department of Duke University, there is something called "Nuclear Chemistry"
"Without this energy from the sun, li