Why is a theory able to predict a phenomena?

[Bodhi Dharma Zen]

Why does this system works? It is assumed that is BECAUSE the theories "reflect reality" (whatever that means), thats why we can make accurate predictions with (some of) them.

Still, take for instance gravity. Is it a force? Is it a distortion of the spacetime continuum? Newtonian mechanics still work, and will work to make a great number of accurate predictions, but this does not render the theory "a true reflection of reality".

Current theories are able to predict with a lot greater degree of accuracy the facts we later observe. Is this an indication of them being "truer"?

[TV's Frank]

Science is not some vague "quest for truth". It is simply a description of nature. General relativity is not "truer" than Newtonian gravity, it is simply a more accurate description of nature. In certain limits, both theories give identical results.

Theories can predict phenomena like this: suppose you have a theory, say Newtonian gravity. You use it to explain, say, the motions of the planets. The predictions of your theory match observations. Awesome. Well, except for the motion of Mercury. It's a little off. So, you wait a couple hundred years, and you come along with General Relativity. Wow! General Relativity correctly describes the motion of Mercury! Sweet! Now you start playing with the theory, looking at the math, seeing what else it predicts. You note, with some interest, that GR predicts that light will bend around massive objects, like the sun. This is something that Newton never even thought of. So, you conclude, if GR is REALLY correct, then not only should it explain the motion of Mercury (which is does), but we should ALSO see this bending of light. This is a never-before-observed phenomenon, so if we go looking for it, we should see it. And we did, and the amount of bending is exactly predicted by GR.

So, in short, scientists predict new phenomena by monkeying around with the mathematics of a theory, and seeing what happens.

[JoeTheJuggler]

"Phenomena" is plural.

As for your question: to some extent, you can say we are selecting better and better theories. The one's that don't predict as well are tossed in favor of the ones that work better.

I think your question is much more philosophical, though. More on the order of "Do our theories say anything about reality, or do they merely describe how our minds perceive reality?"

[Bodhi Dharma Zen]

Science is not some vague "quest for truth". It is simply a description of nature.

A description. The implicit postulate below a description is that we understand what is going on. Furthermore, that we understand it because there is a correspondency between our ideas and the world.

But, note that its also asumed that the correspodency is true because our ideas are a true representation of reality.

General relativity is not "truer" than Newtonian gravity, it is simply a more accurate description of nature. In certain limits, both theories give identical results.

More accurate. This implies that we can have several different descriptions and that some of them (maybe just one) is more accurate because its truer.

This is something that Newton never even thought of. So, you conclude, if GR is REALLY correct, then not only should it explain the motion of Mercury (which is does), but we should ALSO see this bending of light. This is a never-before-observed phenomenon, so if we go looking for it, we should see it. And we did, and the amount of bending is exactly predicted by GR.


GR is REALLY correct... until a new theory comes and render it obsolete (not in its predictive faculties, but our taking it in an epistemic way as "really correct". This is the whole point behind my questions, and any theory can fit. Scientists used to say that "eggs are bad for your heart", now they say otherwise. Mobile phones were considered as dangerous, now they are not... you get the idea.

[Bodhi Dharma Zen]

As for your question: to some extent, you can say we are selecting better and better theories. The one's that don't predict as well are tossed in favor of the ones that work better.

Exactly, we select the "better theories", and they are better because they predict better, nothing more. Can we claim that a theory is like a map (so its not and will never be the territory) and that the better or more accurate the map is the better predictions? At first sight yes, the answer is plain and simple.

But where does it end? Can we have a "final map"?

I think your question is much more philosophical, though. More on the order of "Do our theories say anything about reality, or do they merely describe how our minds perceive reality?"

Exactly, thank you for seeing it. You can add that Im curious about the relation of our language to that what we call "the world". What is an explanation? A set of words that, putted together in certain order, are a representation of our perceptions? Or are we drawing representations about "what is really there, outside our minds"?

[JoeTheJuggler]

A set of words that, putted together in certain order, are a representation of our perceptions? Or are we drawing representations about "what is really there, outside our minds"?

How about this: theories and language reflect our perceptions, but our perceptions evolved in the real world as successful for survival and reproduction. I think we can assume that there is correspondence.

For example, we have words for colors--they differ a little from culture to culture in how we divvy up the visible part of the EM spectrum, but no too much because human eyes are sensitive to the same range of wavelengths. We think of the world as what we see to a great extent. Other animals see, for example, into the UV range--so the world looks very different to them than it does to us. They can even see things that are there that we can't see (patterns on flower petals, for instance).

So our perceptions do reflect at least a part of reality--they're not totally arbitrary.

Our minds can reason out a great deal that we can't perceive (or even imagine--like 4 or more spatial dimensions). I think there is an objective reality that informs our perceptions (and by extension using reason to go farther).

If not, it would be a huge stroke of luck that what we think is reality isn't so far off that actual reality kills us.

[Jeff Corey]

As you probably know, theories cannot be proven to be true. Modus ponens, all that. They are considered to be confirmed if a massive amount of experimental or other empirical data confirm their predictions . Viz, evolution science.

[l0rca]

It seems like your question has elements of induction, philosphical realism/nominalism, and queiries into Popper's falsification ideas. There's a lot in this question, and at the moment, I don't know what approach to take to give you a satisfying answer.

If you're only interested in wondering why theories predict, and not if they have some kind of objective correspondance with reality, then the answer is simple, but hardly satisfying. We axiomize mathematics and logic, assume causes produce effects, as well as some vauge notion of "natural law". These are pure assumptions, though each of them helpful, if not entirely reasonable. Why they tend to work remains up for conjecture.

If you're wondering if science can come to a "soulful" understanding of reality: I don't think so. I think our very experience and understanding is built upon a number of biologically-determined biases about how to interpret and deal with the outside world. I don't think experience and understanding trancsends us at all. The correspondance we have with reality is empirical, yes, but the correspondance is never direct, and we've yet to draw entirely agreeable lines to where our experience of reality ends, and the reality we're experiencing begins. Getting down to it, we may never be able to draw this line, but only better understand the degrees involved.

Sorry for the hazy speculations. Up there's probably mostly psilosophical garbage, but I'm at work.

EDIT: Ehh. to add, it's entirely possible that the brain experiences its own experiences -- that is (if you know of the Multiple Drafts model and other similar material ideas) our consciousness is not continuous, but because of structure and mechanisms, at some point, either fundamental in matter or in a more macrocosmic referance, begins to experience itself on smaller scales -- not in a "cartesian theatre" central way. In such a way, our own experiences are shared, re-experienced, and proliferated throughout the brain. There's still much work to be done before a satisfying explanation for all this can be given, but it helps to open the idea of any material entity being able to, in some universal sense of scale, "experience".

[Schneibster]

Why does this system works? It is assumed that is BECAUSE the theories "reflect reality" (whatever that means), thats why we can make accurate predictions with (some of) them.There are two reasons. First, our universe is such (so far as we've been able to determine) that it has consistency. That is, the most things happen the same way every time, and if they don't, it's because something we didn't notice is different; we can then go look for that something, and we always (so far) have found it. For example, if there's a rock outside my door on the ground today, it will still be there tomorrow unless it was moved by someone or something. If I pick it up and let go of it, it will fall, and it will fall the same way today as it would have last week, and as it will next week. This property of consistency is embodied in physics in symmetries. For example, if I pick the rock up and turn it around, and put it back down, it's still a rock. This illustrates the symmetries of translation (picking it up) and rotation (turning it around).

A brilliant theoretical physicist and mathematician named Emmy Noether showed that these symmetries (specifically, continuous symmetries) each imply a conservation law, and since this is a theorem, she proved it (which you can do with a theorem, being a mathematical construct, unlike a theory). Specifically, she showed (for example) that the symmetry of physical law over translation implies the conservation of momentum, and the symmetry of physical law over rotation implies the conservation of angular momentum.

You will have realized, of course, that the inbuilt consistency of mathematics reflects this apparent consistency of the universe. This is why mathematics is so useful for describing the universe. In fact, if we stick to a few simple rules in our math, if we discover some new way of manipulating the numbers, we almost always find some novel and interesting behavior in the universe that reflects this new way. The basic laws of mathematics, therefore, reflect some basic properties of the universe. And that's no surprise; we chose them carefully so that they would.

What happens is, someone looks at some behavior of the universe, and they develop some math to describe that behavior. This is called, if you will, a "conjecture." Then they explore implications of this conjecture in other areas than the one it was originally developed to explain, and see if they can find anything that makes it inconsistent with reality. If they fail, then it becomes, if you will, a "hypothesis." Finally, they look for implications of behavior that no one has ever checked before. The hypothesis is used to predict novel behavior. Once such a prediction can be made, then they go test it; they go looking for this novel behavior. If they find it, then the hypothesis becomes a theory.

Over time, more and more predictions of a theory are checked. If an inconsistency is found, it may result in a revision of the theory; it may result in the creation of a new theory; or it may result in the rejection of the original theory. The last is extremely unlikely at this stage of things; back in Newton's and Galileo's times, physics was very young, and new ideas were as likely to be completely rejected later as they were to survive. These days, we know enough that most of the theories we make might be revised, or a new theory that describes actions in extremes or conditions the original theory did not account for might be needed, but we rarely find it necessary to reject an entire line of thought.

And remember that as more and more predictions of a theory are checked, if they all come out true, the stronger the support for that theory is. For example, Gravity Probe B is currently checking for indications that Einstein's General Relativity Theory correctly or incorrectly predicts a phenomenon called "frame dragging." If it is correct, then it will be even more strongly supported than it is today; if it is not, then there will be some adjustment, but because GRT correctly predicts the precession of the orbit of Mercury, and correctly predicts the bending of starlight passing near the Sun during an eclipse, it won't be supplanted, it will almost certainly be supplemented.

To understand the genius of Newton and Galileo, consider that Einstein's SRT and GRT, although they are said to supplant the laws of motion and the theory of universal gravitation, in fact, supplement them; the laws of motion are unmeasurably incorrect at ordinary velocities. In other words, the difference between the predictions of the laws of motion and SR at velocities of any macroscopic object we have ever seen is minute enough to be essentially unmeasurable. The only objects we have ever seen moving at relativistic velocities are subatomic particles; and they obey the laws of SR. But for ordinary, everyday objects, the laws of motion are so close an approximation that it is not worthwhile using SR's more complex calculations; we could not measure the difference. Only by the use of the most sensitive measuring instruments are we able to see the effects predicted by GR and SR that differ from the predictions of the laws of motion; atomic clocks, for example.

The second reason that theories are able to predict phenomena is that they are deliberately constructed so that they do; and if they fail to, then they are rejected. We keep only those theories, in other words, that DO accurately describe reality. All others become not-theories.

Still, take for instance gravity. Is it a force? Is it a distortion of the spacetime continuum? Newtonian mechanics still work, and will work to make a great number of accurate predictions, but this does not render the theory "a true reflection of reality".It was never intended to be "a true reflection of reality." It was intended to be an accurate description of reality. And it is. All of them are, within their areas of competency. Newtonian mechanics is not competent when velocities are very high; otherwise, it is. SR and GR are competent, as far as we can tell, for all velocities. Universal gravitation is not competent over very long periods, or in very strong gravity fields; GR is competent, as far as we can tell, for all periods and all field strengths. But SR and GR are very much more complex; so if Newtonian mechanics and universal gravitation give answers that are accurate enough to be useful, that is, if they are used within their areas of competence, then there is no need to use the more complex methods. The question is, how accurate an answer do you need? Choose your method accordingly.

Current theories are able to predict with a lot greater degree of accuracy the facts we later observe. Is this an indication of them being "truer"?No, it is an indication of them being more accurate. But I think that was obvious from what I have already written.

[Dave1001]

Why does this system works? It is assumed that is BECAUSE the theories "reflect reality" (whatever that means), thats why we can make accurate predictions with (some of) them.

Still, take for instance gravity. Is it a force? Is it a distortion of the spacetime continuum? Newtonian mechanics still work, and will work to make a great number of accurate predictions, but this does not render the theory "a true reflection of reality".

Current theories are able to predict with a lot greater degree of accuracy the facts we later observe. Is this an indication of them being "truer"?

I'm also curious about tools we have to assess the degree to which these correlations might be completely random. I assume there's a possibity of this being the case that's greater than zero? How do we make or attempt to make these determinations?

[cafink]

Exactly, we select the "better theories", and they are better because they predict better, nothing more. Can we claim that a theory is like a map (so its not and will never be the territory) and that the better or more accurate the map is the better predictions? At first sight yes, the answer is plain and simple.

But where does it end? Can we have a "final map"?

As the late Carl Sagan explained it, the scientific method "helps us determine not absolute truth, only asymptotic approaches to the truth--never there, just closer and closer, always finding vast new oceans of undiscovered possibilities when we have made tiny forays into the island on this great sea of unknowing."

[Dave1001]

It seems like your question has elements of induction, philosphical realism/nominalism, and queiries into Popper's falsification ideas. There's a lot in this question, and at the moment, I don't know what approach to take to give you a satisfying answer.

If you're only interested in wondering why theories predict, and not if they have some kind of objective correspondance with reality, then the answer is simple, but hardly satisfying. We axiomize mathematics and logic, assume causes produce effects, as well as some vauge notion of "natural law". These are pure assumptions, though each of them helpful, if not entirely reasonable. Why they tend to work remains up for conjecture.

If you're wondering if science can come to a "soulful" understanding of reality: I don't think so. I think our very experience and understanding is built upon a number of biologically-determined biases about how to interpret and deal with the outside world. I don't think experience and understanding trancsends us at all. The correspondance we have with reality is empirical, yes, but the correspondance is never direct, and we've yet to draw entirely agreeable lines to where our experience of reality ends, and the reality we're experiencing begins. Getting down to it, we may never be able to draw this line, but only better understand the degrees involved.

Sorry for the hazy speculations. Up there's probably mostly psilosophical garbage, but I'm at work.

EDIT: Ehh. to add, it's entirely possible that the brain experiences its own experiences -- that is (if you know of the Multiple Drafts model and other similar material ideas) our consciousness is not continuous, but because of structure and mechanisms, at some point, either fundamental in matter or in a more macrocosmic referance, begins to experience itself on smaller scales -- not in a "cartesian theatre" central way. In such a way, our own experiences are shared, re-experienced, and proliferated throughout the brain. There's still much work to be done before a satisfying explanation for all this can be given, but it helps to open the idea of any material entity being able to, in some universal sense of scale, "experience".

Very well-written. This assessment most closely matches my own, although I doubt I'd be able to articulate it as elegantly as I0rca

[Bodhi Dharma Zen]

How about this: theories and language reflect our perceptions, but our perceptions evolved in the real world as successful for survival and reproduction. I think we can assume that there is correspondence... ... If not, it would be a huge stroke of luck that what we think is reality isn't so far off that actual reality kills us.

Good way to put it. I agree. Now, this would pressupose that our thinking is delimited by our biology. We have being able to think "outside our humanity" (so to speak) by extrapolating, deducing, creating tools to enhance our perceptions, etc. Still, our words are based on our natural ways for perception.

I believe this is why its so difficult to talk about, or understand, things like theoretical physics, GR and SR, Quantum mechanics, and so on. We simply lack the appropriate concepts because our "normal every day life and perceptions" limit what we can think, or our use of language.

That said, it is interesting this relation between language, meanings and the so called "external reality". And I put it in between " " because EXTERNAL REALITY is a concept, not a perception. We deduce its existence, but we cant see it or touch it or smell it.

[Bodhi Dharma Zen]

As you probably know, theories cannot be proven to be true. Modus ponens, all that.

But my point is that they are considered true. Of course, truth is truth, and an approximation to it is simply that, an approximation.

Now, the interesting part, IMO, is that when we say that we have an approximate truth, we are implying that there is a final truth, whatever that means.

I

[Bodhi Dharma Zen]

In such a way, our own experiences are shared, re-experienced, and proliferated throughout the brain. There's still much work to be done before a satisfying explanation for all this can be given, but it helps to open the idea of any material entity being able to, in some universal sense of scale, "experience".

I agree. This is the more natural explanation I can think of. That said, its intriguing the relation between the ideas generated by "something" that can arrange those experiences in a meaningful way, and their cause.

[Bodhi Dharma Zen]

... What happens is, someone looks at some behavior of the universe, and they develop some math to describe that behavior. This is called, if you will, a "conjecture."...

... The question is, how accurate an answer do you need? Choose your method accordingly.

Thoughtful post, I will try to answer you when I have more time. Just to brief comments. To the first paragraph, yes, I would say that all we have, and can aspire to have, are conjectures, nothing more. We can then build theories, but our theories are just succesful, or not, in explaining (predicting) observations. No "reality" nor "truth" can be deduced by them, which leads us to the last paragraph I choose from your response. :)

[Bodhi Dharma Zen]

I'm also curious about tools we have to assess the degree to which these correlations might be completely random. I assume there's a possibity of this being the case that's greater than zero? How do we make or attempt to make these determinations?

Exactly!

[Bodhi Dharma Zen]

As the late Carl Sagan explained it, the scientific method "helps us determine not absolute truth, only asymptotic approaches to the truth--never there, just closer and closer, always finding vast new oceans of undiscovered possibilities when we have made tiny forays into the island on this great sea of unknowing."

The problem with this view, IMO, is that we pressupose that there is something like "a final truth". I cant buy that. We can, or cant, predict what happens next, but only using artificial models, which happen to be related, somehow, to "that" what is "beyond us".

[cafink]

"That what is beyond us," as you put it, is the "final truth." As science advances, our models of this truth become increasingly accurate. We'll never know everything that there is to know about it, but we learn more and more every day, forever coming closer and closer to that truth.

[Bodhi Dharma Zen]

"That what is beyond us," as you put it, is the "final truth." As science advances, our models of this truth become increasingly accurate. We'll never know everything that there is to know about it, but we learn more and more every day, forever coming closer and closer to that truth.

How close? how do you measure this?

IMO, what is happening is similar to the old "the map is not the territory". It doesnt matter how well you can predict something, what you are doing is making a map about "that other thing", and this map (or collection of maps) will always be artificial, full of ad hoc conjectures and, to a point, arbitrary.

[cafink]

You measure this by comparing your new model (or "map") of reality to your old model of reality. If the new model more accurately reflects your empirical observations of the world around you, then it's safe to say that the new model closer to the truth. If it does not, then you ought to stick with the old model.

I think your map analogy is apt. A map is not a perfect, flawless representation of the territory. But it's close enough to be useful in many practical applications, especially since virtually all of the Earth's surface has been explored. Imagine what a map of the Earth would have looked like before Christopher Columbus. It would have had many errors and omissions. Today's maps more accurately reflect the Earth thanks to the work of explorers, just as today's scientific theories more accurately reflect the "truth" thanks to the work of scientists.

But it's not arbitrary, as you claim. Scientists can compare proposed theories to existing theories, and select the one that more closely reflects their empirical observations. There is not always a perfect process, but it's not arbitrary.

[Dave1001]

Bodhi, I take it like me that you don't want to die and are willing to do whatever it takes to maximize your apparent odds of persistence? Cause I think that's what we're left with. =)

[Schneibster]

How close? how do you measure this?

IMO, what is happening is similar to the old "the map is not the territory". It doesnt matter how well you can predict something, what you are doing is making a map about "that other thing", and this map (or collection of maps) will always be artificial, full of ad hoc conjectures and, to a point, arbitrary.We're drifting into philosophy here, but let me make a couple of points. I saw your earlier post, BDZ, but you made much the same point here and more articulately, I think.

What of truth there is for us to interact with is an electrical signal passed down nerves to our brains. There is nothing more. Even the "true" existence of those brains is based upon observations using that equipment. In other words, "I think therefore I am" is about all we can ever know of "truth," and even that is conjectural, because my memories of the times a second, or a lifetime, ago, might have just now been created and presented to "me," whatever "I" might be.

So it's pretty apparent that to even discuss "the real world," we are making a raft of assumptions that boil down to, I'm real, events in my memory are real, what my senses tell me is real, and you're all real. Now, you can refuse to accept those assumptions; but if you do, as Camus pointed out, that is the path of suicide, by starvation and thirst if nothing more dire. If you choose to live, then you must choose to interact with this world, and to treat it as if it is "reality," whatever that might be, to obtain food and water foremost, but also to obtain stimulation for your mind, without which human minds apparently can be damaged if they are separated from it for too long; we know this from sensory deprivation experiments.

So, given that all of that is so, and given that we must accept these assumptions, we have to consider how we will treat other assumptions, and we must look to the information of our senses to tell us what we can expect to encounter. And when we look at that information, what we find is that the information of our senses describes a world whose foremost attribute is that it is consistent; I have discussed that consistency above. The rest of that prior post follows from this.

So if you want any access to anything anyone might call "truth," ultimately, that is closed to you. The most you can hope for is accuracy. And science offers that, above all. What you do with that is your own lookout.

[Schneibster]

How close? how do you measure this?

IMO, what is happening is similar to the old "the map is not the territory". It doesnt matter how well you can predict something, what you are doing is making a map about "that other thing", and this map (or collection of maps) will always be artificial, full of ad hoc conjectures and, to a point, arbitrary.We're drifting into philosophy here, but let me make a couple of points. I saw your earlier post, BDZ, but you made much the same point here and more articulately, I think.

What of truth there is for us to interact with is an electrical signal passed down nerves to our brains. There is nothing more. Even the "true" existence of those brains is based upon observations using that equipment. In other words, "I think therefore I am" is about all we can ever know of "truth," and even that is conjectural, because my memories of the times a second, or a lifetime, ago, might have just now been created and presented to "me," whatever "I" might be.

So it's pretty apparent that to even discuss "the real world," we are making a raft of assumptions that boil down to, I'm real, events in my memory are real, what my senses tell me is real, and you're all real. Now, you can refuse to accept those assumptions; but if you do, as Camus pointed out, that is the path of suicide, by starvation and thirst if nothing more dire. If you choose to live, then you must choose to interact with this world, and to treat it as if it is "reality," whatever that might be, to obtain food and water foremost, but also to obtain stimulation for your mind, without which human minds apparently can be damaged if they are separated from it for too long; we know this from sensory deprivation experiments.

So, given that all of that is so, and given that we must accept these assumptions, we have to consider how we will treat other assumptions, and we must look to the information of our senses to tell us what we can expect to encounter. And when we look at that information, what we find is that the information of our senses describes a world whose foremost attribute is that it is consistent; I have discussed that consistency above. The rest of that prior post follows from this.

So if you want any access to anything anyone might call "truth," ultimately, that is closed to you. The most you can hope for is accuracy. And science offers that, above all. What you do with that is your own lookout.

[Bodhi Dharma Zen]

You measure this by comparing your new model (or "map") of reality to your old model of reality.

But the only method to measure it would be to compare it against "the world". Problem: "The world" is an assumption, a theoretical account, a theory if you like.

A map is not a perfect, flawless representation of the territory. But it's close enough to be useful in many practical applications, especially since virtually all of the Earth's surface has been explored. Imagine what a map of the Earth would have looked like before Christopher Columbus. It would have had many errors and omissions. Today's maps more accurately reflect the Earth thanks to the work of explorers, just as today's scientific theories more accurately reflect the "truth" thanks to the work of scientists.

Ok, this would serve to add to my point. I believe you are correct when you say that its purpose its to be useful in practical applications. But jumping from here to claim that a map is more accurate is a no go. Taking your example about the earth, when would a map is "accurate enough"? when it reaches a resolution of 100m? 1m? 1cm? when it is a 3D representation? when it includes relations as the value of money or the power of a smile?

But it's not arbitrary, as you claim. Scientists can compare proposed theories to existing theories, and select the one that more closely reflects their empirical observations. There is not always a perfect process, but it's not arbitrary.

Oh I think it is, but I need to explain it further. Lets get back to the world map. If I use certain scale (say cms instead of inches), Im being arbitrary. The size of the map is arbrtrary, the points I take interest in (say, there are political maps or climate maps) are arbitrary too.

[Bodhi Dharma Zen]

We're drifting into philosophy here, but let me make a couple of points. I saw your earlier post, BDZ, but you made much the same point here and more articulately, I think.

Thanks, it is difficult to put in words what I think, first, because its a complex subject, secondly, because English is not my first language.


So it's pretty apparent that to even discuss "the real world," we are making a raft of assumptions that boil down to, I'm real, events in my memory are real, what my senses tell me is real, and you're all real. Now, you can refuse to accept those assumptions; but if you do, as Camus pointed out, that is the path of suicide, by starvation and thirst if nothing more dire. If you choose to live, then you must choose to interact with this world, and to treat it as if it is "reality," whatever that might be, to obtain food and water foremost, but also to obtain stimulation for your mind, without which human minds apparently can be damaged if they are separated from it for too long; we know this from sensory deprivation experiments.

Oh, believe me, I treat it as real. In fact, in everyday language the world is as real as it can get. It is objective, beyond my senses, its not related to the existence of my perceptions, etc. To a point Im the usual realist, I guess. But remember that we are only talking in the everyday language.

When I go deeper I begin to see all kind of inconsistencies, digging in nature one enter realms in which "everyday logic" does not apply (like in my thread about gravity) ;).

Now, going still deeper I see that language plays a fundamental role. Its not about the world, but about what we mean by "the world", about what is "to mean". Anyway, reflections, reflections.

... And when we look at that information, what we find is that the information of our senses describes a world whose foremost attribute is that it is consistent; I have discussed that consistency above. The rest of that prior post follows from this.

Absolutely agree. In my worldview, I name that "consistency" the invariants behind our perceptions. Thats why Im not an idealist, I believe I understand that, even when Im unable to see what we call the world "as it is" (the noumena), the phenomena constantly reminds us that its there.

So if you want any access to anything anyone might call "truth," ultimately, that is closed to you. The most you can hope for is accuracy. And science offers that, above all. What you do with that is your own lookout.

Well, Im not married with any "truth". In fact, I used the concept on purpose, in part to try to have an interesting conversation.

[Tumblehome]

A theory is able to predict phenomena only as far as we test it. Calling a theory The Truth is a human foible. It really means "the truth as far as we know" because we very likely haven't conceived of all the ways to test it. At one time, our experience taught us that the Sun orbited the Earth, and that was The Truth until we had more sophisticated knowledge to test it.

That doesn't mean theories are useless. They serve their purpose until they can be improved on. To use your map analogy (which cafink did very well, but since I already wrote this, I'll do it anyway :)), the maps that the early explorers used were horrendously wrong in some places, yet they still allowed the explorers to get to the general area. Once there, they could refine the maps, or completely redraw them if necessary.

[cafink]

But the only method to measure it would be to compare it against "the world". Problem: "The world" is an assumption, a theoretical account, a theory if you like.

The world is a "theory"? I'm not sure I understand. If the world is a theory, then it's the most well-supported theory in history, being ever-supported by empirical evidence for as long as humans have been around.

Ok, this would serve to add to my point. I believe you are correct when you say that its purpose its to be useful in practical applications. But jumping from here to claim that a map is more accurate is a no go. Taking your example about the earth, when would a map is "accurate enough"? when it reaches a resolution of 100m? 1m? 1cm? when it is a 3D representation? when it includes relations as the value of money or the power of a smile?

Whether or not your map is accurate enough depends on what you'd like to use it for. To use the example of an actual map, if I want to drive to another state, a simple U.S. highway map will do. But if I want to drive to a particular town within that state, I'll need a more detailed regional street map.

Again, our "map" of reality will never be perfect, but it gets closer and closer to perfection (Sagan's "asymptotic approach to the truth") all the time. The closer to perfection it is, the more amazing things we can use it for.

[Schneibster]

Thanks, it is difficult to put in words what I think, first, because its a complex subject, secondly, because English is not my first language.No criticism intended; it was more my perception that your thoughts might have been clearer in the later post.

Oh, believe me, I treat it as real. In fact, in everyday language the world is as real as it can get. It is objective, beyond my senses, its not related to the existence of my perceptions, etc. To a point Im the usual realist, I guess. But remember that we are only talking in the everyday language.

When I go deeper I begin to see all kind of inconsistencies, digging in nature one enter realms in which "everyday logic" does not apply (like in my thread about gravity) ;).Well, the really interesting thing is, whenever we find one of these inconsistencies, and really dig at it, and you can figure that any physicist worth his salt is going to pick one of them out and do just exactly that, when we're done explaining why it's inconsistent, we find an underlying consistent explanation; perhaps with similar flaws, but those flaws will be in places we never even thought to look, or perhaps didn't even know existed, when we were contemplating the original flaw.

The logic of the world we see and taste and touch and smell and hear, is not necessarily the logic of the world. It is, so far as we've ever been able to tell, all consistent; it's just that it doesn't appear consistent at the level we sense it at. Overall, it does; but examine it really closely, and you find out that the obvious, apparently consistent explanations you make up to explain it all have underlying inconsistencies that only appear when you think about things that we don't encounter much: things that are very massive, or that move very fast, or that are very small.

One of those assumptions is that the explanations for those things that are massive or fast or small do have consistent explanations, and so far, as far as we've been able to figure out, they do. GR is one of those explanations. There are still small inconsistencies in it; but overall, again, it's consistent, and the things it predicts are the things we see (and can measure).

What you're really looking for here isn't consistency, but completeness. And that's a very different thing. We have reason to believe that mathematics, at least, cannot be both complete and consistent; there is more than just belief, you can actually prove it mathematically. The method for doing so is called Godel's Theorem. So it's entirely possible that we'll go on forever searching for completeness and never find anything at the end but an infinite regress. We are, of course, nowhere near there now.

Now, going still deeper I see that language plays a fundamental role. Its not about the world, but about what we mean by "the world", about what is "to mean". Anyway, reflections, reflections.That's why I say it's more philosophy than science.

Absolutely agree. In my worldview, I name that "consistency" the invariants behind our perceptions. Thats why Im not an idealist, I believe I understand that, even when Im unable to see what we call the world "as it is" (the noumena), the phenomena constantly reminds us that its there.Two points I'd make here:
1. That consistency is what we perceive. It's not a characteristic of those perceptions, however, if you accept the assumption that we're real and our perceptions are a reflection of some "reality" "out there."
2. Noumena, according to my understanding of the concept, are what is in the mind: the only things we can really be sure of because we experience them directly. Phenomena, on the other hand, encompass not merely all that we sense, but all that happens whether we can, or even theoretically could, sense it or not. In other words, not merely the reality we perceive, but the reality that IS, is made up of phenomena. If you have a different understanding, I'd very much like to see a reference; not because I question your statement, but because I wish to learn more.

Well, Im not married with any "truth". In fact, I used the concept on purpose, in part to try to have an interesting conversation.You succeeded, I think. ;)

[JoeTheJuggler]

But the only method to measure it would be to compare it against "the world". Problem: "The world" is an assumption, a theoretical account, a theory if you like.

I think denying objective reality ("the world") is at least AS much an assumption as postulating that it exists.

The finger pointing at the moon is not itself the moon, but that doesn't mean there is no moon.

[Soapy Sam]

"Phenomena" is plural.

Except in the case of singular phenomena.

[Bodhi Dharma Zen]

A theory is able to predict phenomena only as far as we test it. Calling a theory The Truth is a human foible. It really means "the truth as far as we know" because we very likely haven't conceived of all the ways to test it.

Then again, its not "a truth". In this sense, what Im trying to say, is that "truths" are myths, another kind of theories, if you like, but thats it.

At one time, our experience taught us that the Sun orbited the Earth, and that was The Truth until we had more sophisticated knowledge to test it.

This is perfect to illustrate my point. The Sun effectively rises on the mornings and turn around us. Its not an illusion, its as real and tangible and true as that the Earth is going around the Sun. Both postulates are "true" in certain context, thats all. None of them is "truer" per se.

That doesn't mean theories are useless. They serve their purpose until they can be improved on. To use your map analogy (which cafink did very well, but since I already wrote this, I'll do it anyway :)), the maps that the early explorers used were horrendously wrong in some places, yet they still allowed the explorers to get to the general area. Once there, they could refine the maps, or completely redraw them if necessary.

Exactly, and as I argued before, a map is necessarily arbitrary and it has to have a purpose. Its accuracy is measured against its success to accomplish that purpose. No more and no less.

[Cuddles]

Is there any particular this is on the science forum and not the philosophy forum? Vague handwaving about the meaning of reality has no place here.

[Bodhi Dharma Zen]

The world is a "theory"? I'm not sure I understand. If the world is a theory, then it's the most well-supported theory in history, being ever-supported by empirical evidence for as long as humans have been around.

It is, that is why is sometimes difficult to see it as a theory, its so well stablished and "obvious" that is like saying that the Sun doesnt rise every morning.

Whether or not your map is accurate enough depends on what you'd like to use it for. To use the example of an actual map, if I want to drive to another state, a simple U.S. highway map will do. But if I want to drive to a particular town within that state, I'll need a more detailed regional street map.

And so, its accuracy is measured against its success (or lack of), not any world.

Again, our "map" of reality will never be perfect, but it gets closer and closer to perfection (Sagan's "asymptotic approach to the truth") all the time. The closer to perfection it is, the more amazing things we can use it for.

This is what I object. The very sense of being "closer to perfection" implies that there is such a thing as "a map that is reality". That representations ARE the very thing that was being represented, and this is a clear logic mistake. IMO.

[Bodhi Dharma Zen]

Is there any particular this is on the science forum and not the philosophy forum? Vague handwaving about the meaning of reality has no place here.

You can change it to the philosophy forum, maybe it was my mistake, but I cant see how we can do science without having a clear notion about the epistemic problems that underly the reality of the world you are experimenting with ;)

[Bodhi Dharma Zen]

One of those assumptions is that the explanations for those things that are massive or fast or small do have consistent explanations, and so far, as far as we've been able to figure out, they do. GR is one of those explanations. There are still small inconsistencies in it; but overall, again, it's consistent, and the things it predicts are the things we see (and can measure).

Yes, thats why I love science, somehow our assumptions have been rewarded with increasing consistency (higher order?)

What you're really looking for here isn't consistency, but completeness. And that's a very different thing... ...That's why I say it's more philosophy than science.

You are right, and point taken, I have no problems is some mod decides to change the thread to the philosophy forum... except that religion is in the same forum!!!!

(TO THE MODS, ADMINS AND ETC, I REALLY THINK THAT PHILOSOPHY IS CLOSER TO SCIENCE THAT TO RELIGION, and sorry for the caps).

Two points I'd make here:
1. That consistency is what we perceive. It's not a characteristic of those perceptions, however, if you accept the assumption that we're real and our perceptions are a reflection of some "reality" "out there."

I dont know what to accept, because even when that model about "us" being real and "the world" being real is acceptable for everyday use, I think its consistencies can be explained with another kind of model.

2. Noumena, according to my understanding of the concept, are what is in the mind: the only things we can really be sure of because we experience them directly. Phenomena, on the other hand, encompass not merely all that we sense, but all that happens whether we can, or even theoretically could, sense it or not. In other words, not merely the reality we perceive, but the reality that IS, is made up of phenomena. If you have a different understanding, I'd very much like to see a reference; not because I question your statement, but because I wish to learn more.

Actually, its the other way around. Phenomena is the world as we see it, all perceptions and feelings and EVEN concepts and theories are here. Noumena is what is beyond our perceptions, that what makes them consistent, if you like. ;)

[Bodhi Dharma Zen]

I think denying objective reality ("the world") is at least AS much an assumption as postulating that it exists.

You have a very good point here. Both are assumptions, and we choose the one that explains more data to us. The map that we use is the map that give us the results we expect ;)

[Schneibster]

Actually, its the other way around. Phenomena is the world as we see it, all perceptions and feelings and EVEN concepts and theories are here. Noumena is what is beyond our perceptions, that what makes them consistent, if you like. ;)I did a little research, and it turns out we're both right (although you're talking about something that is beyond either scientific proof or even the ability to conceive of it). I am talking about Kant's positive noumena; you are talking about his negative noumena. In my view, however, in contrast to Kant's (and apparently yours), noumena are the things of the mind: thoughts and feelings. The software, in other words, whereas the phenomena are the hardware. The two can even coincide: the noumenon of a thought or feeling I am having can correspond to the phenomenon of the pattern of electrical activation of neurons in my brain, and chemical changes that stimulate, are stimulated by, moderate, or are moderated by that electrical activity. Kant, after all, didn't have the advantage of modern neuroscience or information theory.

(I'll point out for your reference that noumena and phenomena are plural forms; noumenon and phenomenon are the singular forms. Phenomena should therefore be used with the plural article, are, as should noumena; you used them with the singular article, is. A little piece to add to your lexicon.)

[Bodhi Dharma Zen]

I did a little research, and it turns out we're both right

Good. And points taken (regarding my use of some words), thanks. Im also interested in your opinion about my conclusion regarding maps. Please allow me to quote myself ;)

"Exactly, and as I argued before, a map is necessarily arbitrary and it has to have a purpose. Its accuracy is measured against its success to accomplish that purpose."

[Schneibster]

Well, I guess that's pretty much what I was saying- except, you see, the map is all we ever get.

One more note: the British often use the plural article for a singular organization; for example, "the government are..." whereas Americans generally use the singular: "the government is..."

[Tumblehome]

Then again, its not "a truth". In this sense, what Im trying to say, is that "truths" are myths, another kind of theories, if you like, but thats it.



This is perfect to illustrate my point. The Sun effectively rises on the mornings and turn around us. Its not an illusion, its as real and tangible and true as that the Earth is going around the Sun. Both postulates are "true" in certain context, thats all. None of them is "truer" per se.



Exactly, and as I argued before, a map is necessarily arbitrary and it has to have a purpose. Its accuracy is measured against its success to accomplish that purpose. No more and no less.


I agree with you in that our version of The Truth changes. But that doesn't mean that nothing is true. Surely some things have to be true, otherwise the Universe would not be able to operate the way it does. It runs under a certain set of laws, or truths. It's our perception of those truths that turn out to be flawed or completely wrong, not the truths themselves.

ETA: Just because the ancients thought the Sun orbited the Earth was true, from their perspective, doesn't make it as true as the Earth orbiting the Sun. If you could take an ancient human and show him what we know today, he should realize he was wrong. We only know better today because our perspective is better. The map is more refined.

[Bodhi Dharma Zen]

I agree with you in that our version of The Truth changes. But that doesn't mean that nothing is true. Surely some things have to be true, otherwise the Universe would not be able to operate the way it does. It runs under a certain set of laws, or truths. It's our perception of those truths that turn out to be flawed or completely wrong, not the truths themselves.

ETA: Just because the ancients thought the Sun orbited the Earth was true, from their perspective, doesn't make it as true as the Earth orbiting the Sun. If you could take an ancient human and show him what we know today, he should realize he was wrong. We only know better today because our perspective is better. The map is more refined.

Curious, because I feel exactly the opposite. Our version of "The Truth" its destined to change because its flawed right from the beginning. We can have truths, some of them more perdurable than others, but everyone of them just relative to certain calculations, or POVs.

Now, all we have is certain invariables, or constants, that led us postulate (in the first place) that the world is not something that occurs in our heads. There is an objective reality of some sort. And by this I mean independent from our observations, nothing more.

That said, its characteristics will vary depending on the POV of the individual who ask a question. Our maps can be only refined in the sense they provide useful answers to particular questions, but they are not "approximations" to anything else.

Movement is relative, so both propostions are true (in the whole sense of the word). The sun rises in the mornings, and the earth travels around the sun. :)

[Tumblehome]

Curious, because I feel exactly the opposite. Our version of "The Truth" its destined to change because its flawed right from the beginning. We can have truths, some of them more perdurable than others, but everyone of them just relative to certain calculations, or POVs.

Now, all we have is certain invariables, or constants, that led us postulate (in the first place) that the world is not something that occurs in our heads. There is an objective reality of some sort. And by this I mean independent from our observations, nothing more.

That said, its characteristics will vary depending on the POV of the individual who ask a question. Our maps can be only refined in the sense they provide useful answers to particular questions, but they are not "approximations" to anything else.

Movement is relative, so both propostions are true (in the whole sense of the word). The sun rises in the mornings, and the earth travels around the sun. :)


While ancient man was thinking the Sun orbited a static Earth, the Earth was in fact orbiting the Sun. How does that make his conclusion true, other than in his own mind? His conclusion conflicted with the objective reality independent of his observations--that is, it was wrong--because his POV was too limited.

Does relativity really say that ancient man was correct, or does it say he was fooled by a limited POV?

[DanishDynamite]

Why does this system works? It is assumed that is BECAUSE the theories "reflect reality" (whatever that means), thats why we can make accurate predictions with (some of) them.

Still, take for instance gravity. Is it a force? Is it a distortion of the spacetime continuum? Newtonian mechanics still work, and will work to make a great number of accurate predictions, but this does not render the theory "a true reflection of reality".

Current theories are able to predict with a lot greater degree of accuracy the facts we later observe. Is this an indication of them being "truer"?
Philosophically, it doesn't matter why scietific theories predict actual reality.

The fact is, that those theories which do so, are spared the butchers knife, and those that don't have their throats cut.