Logic without evidence

[JetLeg]

Hi.

1)Can one use logic without using evidence?
2)What would that be like?
3)Can one live using logic but not evidence?

[Third Eye Open]

P1. Jetleg is a jerk.
P2. Jerks have blue hair.
C. Jetleg has blue hair!


::::::::::::POOOF:::::::::: LOGIC!

[D'rok]

Math.

[drkitten]

Hi.

Can one use logic without using evidence? What would that be like?

Sure can. Arguably, that's what mathematics is, since we don't have any actual evidence to support most of the axioms underlying mathematics.

An example of logic without evidence.

Premise 1 : All florgnaps are binklefritzes.
Premise 2: No binklefritzes are hofferdinks.
Conclusion : No florgnaps are hofferdinks.

The conclusion follows from the premises, irrespective from the state of the world.

From this I conclude that if Sam believes that he owns a florgnap that is also a hofferdink, but also believes the two premises listed above, that Sam is incorrect in at least one of his beliefs. Again, I have no evidence as to which, but mere logical tells us of his inconsistency.

[Denver]

I'm not certain what you're asking. But, in formal logic, you can say something like:

If A is true, then B is true.

Is that a valid statement? Well, it is a 'given' in this case. So let's say it is. But how do you then use it?

If someone now tells you A is true (lets say that is evidence of A), you can use the above to show B is true.

If you don't have evidence of A (it is not given), but you have evidence of B (it is given instead), you can now say that A might be true.

But if neither A nor B is given, you can't use your single IF statement for anything more. So in this sense, you can't get much use out of your logic without some evidence beyond what it already says.

However, you might also have "If B is true, then C is true". So now, even though you don't have evidence of A or B or C, you can say that if "A if true, then C is true".

So by these definitions from the OP, yes, you can use logic without using evidence, using the definition of logic (the rules) and evidence (the things in the rules) above.

I'm guessing this may not be what you're asking though?

[LightningStrike]

Hi.

1)Can one use logic without using evidence?
2)What would that be like?
3)Can one live using logic but not evidence?

1) Yes consciousness without self reflection= no thought
2) Conscious immersion in (the pleasure of) the senses and non-senses*.
3) Yes, see that the body and consciousness are in total harmony.

*non-senses refers here to the inner sensational reality of wellbeing and love

The thinker who requires evidence is left behind as useless and disappears leaving consciousness and the senses as the reality of now. I am logical.

[dogjones]

Hi.

1)Can one use logic without using evidence?
2)What would that be like?
3)Can one live using logic but not evidence?

1. Yes. This is deductive logic, where validity is all that matters, ie, the conclusion following from the premises, regardless of the truth of same.

2. Not much would get done.

3. A man's gotta eat.

[Pure Argent]

Yes, you can. What does it matter?

[Bikewer]

For quite a long time, deductions made by "pure reason" were felt to be superior to empirical investigations. This led to such wonders as St. Augustine's "proofs", of course.

[leafman91]

Hi.

1)Can one use logic without using evidence?
2)What would that be like?
3)Can one live using logic but not evidence?

You can indeed. So long it isn't bad logic, that is.

[yy2bggggs]

I disagree with math as an example. Mathematics doesn't use logic and not evidence--it uses logic as evidence.

Logic is quite simply the appropriate thing to use for evidence with regard to mathematical claims due to what is being claimed.

[nescafe]

Hi.

1)Can one use logic without using evidence?
Yes.
2)What would that be like?
Mathematics.
3)Can one live using logic but not evidence?
Non sequitor.