logic

[forufes]

i say

"our logic is based on our experience"

my friend tells me to stop talking from my ass and prove it.

i ask him to disprove it, he says the burden of proof is on me, cuz i'm making a claim.

i pointed out that hes also making a claim by opposing me(that logic isn't based on experience), and that in reality proof is on the one making the extraordinary claim, and mine was simple common sense.

he said that it's common sense for me, but i can't objectively state that.

so, he kept demanding "proof".

 

and while he's a total ass, and i should've ripped his bones apart, i just shut up since it's a fight of words.

 

i even asked him to giv me an exampe of a logical statement, so that i show him that it's based on his experience, and that under different experiences, it won't be logical anymore, and he refused.

 

the implication he was running away is that what is logical isn't necessary right, since our experience is not only different, it's also growing.

 

so is there any proof? should there be proof for such simple statements? is proof the only was of proving the consistency of logic?

[the tree]

The burden of proof is certainly on you.

 

i even asked him to giv me an exampe of a logical statement, so that i show him that it's based on his experience, and that under different experiences, it won't be logical anymore, and he refused.

Try any of these.

• [ P or not(P) ] is always true.
  
• [ P and not(P) ] is always false.
  
• If all A's are X's and there is exists at least one A, then there exists at least one X.
  
• [ if P then Q ] = [if not(Q) then not(P) ]
  
• [if P then Q ] = [ Q or not(P) ]
  
• if A=B and B=C and C=D and D=E, and equality is transitive, then A=E
  

should there be proof for such simple statements?

Unquestionably.

is proof the only was of proving the consistency of logic?

I think, for everyone's sake, you might not want to ask that.

[forufes]

The burden of proof is certainly on you.

but why?

you can drive your opponent crazy by treating every sentence of his as a statement then demanding proof for it..

 

Try any of these.

• [ P or not(P) ] is always true.
  
• [ P and not(P) ] is always false.
  
• If all A's are X's and there is exists at least one A, then there exists at least one X.
  
• [ if P then Q ] = [if not(Q) then not(P) ]
  
• [if P then Q ] = [ Q or not(P) ]
  
• if A=B and B=C and C=D and D=E, and equality is transitive, then A=E
  

sorry they all went over my head, couldn't understand how any of them work:embarass:

 

Unquestionably.

yeah well proof itself is comprised of simple statements which don't require proof.

but i think my statement wasn't simple enough, does that mean i should've put it in terms of A's and B's for it to be simple enough not to require proof?

I think, for everyone's sake, you might not want to ask that.

i thought proof is built UPON logic, you can't explain logic by proof that is understood and evaluated by (once again) by logic.

 

well, unless some logic was explainable and some logic isn't, as in logic is built upon itself, and that should be explained by some sort of proof, but in the end, you've got no proof that if a=b and b=c then a=c, but the blockhead in front of you shouldn't even ask for it.

[Mr Skeptic]

i say

"our logic is based on our experience"

my friend tells me to stop talking from my ass and prove it.

i ask him to disprove it, he says the burden of proof is on me, cuz i'm making a claim.

i pointed out that hes also making a claim by opposing me(that logic isn't based on experience), and that in reality proof is on the one making the extraordinary claim, and mine was simple common sense.

 

The burden of proof is on whoever is making the claim. Requesting that someone fulfill their burden of proof, is not a claim. Both "common sense" and "extraordinary" claims require proof when made, but the "extraordinary" claims require more proof.

 

i even asked him to giv me an exampe of a logical statement, so that i show him that it's based on his experience, and that under different experiences, it won't be logical anymore, and he refused.

 

How about this one:

A person on a show won a prize, and has a chance to pick his prize out of 1 car and 2 goats, which are behind closed doors. He prefers the car. Once he picks a door, the show host opens one of the doors he did not select, containing a goat (never opens the one with the car). He then offers the contestant the chance to switch doors. Is the contestant better off switching doors? What are his chances of getting the car?

 

so is there any proof? should there be proof for such simple statements? is proof the only was of proving the consistency of logic?

 

In logic, proof has to be done for the simplest of things. Logic is a formal form of thought.

[the tree]

sorry they all went over my head, couldn't understand how any of them work

Really? They aren't that difficult. Each letter represents a well defined proposition which can be said to be true or false. The first bullet says that all propositions are either true or false (e.g. Socrates is either mortal or not mortal), the second says that they are never both (e.g. Socrates is not both mortal and not mortal).

 

i thought proof is built UPON logic, you can't explain logic by proof that is understood and evaluated by (once again) by logic.

Not completely. Proofs should be logical, but if they have anything to do with the real world then they need to be somewhat empirical.

 

Deductive proofs are built entirely upon logic.

• Socrates is a man
  
• All men are mortal
  
• Therefore Socrates is motal
  

Is a deductive proof, with two postulates assumed to be true for the sake of the argument. This is purely logical.

 

On a more day to day basis, proofs are inductive - that is that they are built on evidence and a philosophical notion known as the principle of induction.

• Of the five thousand ravens surveyed, all of them were black.
  
• Therefore ravens are black
  

This is a combination of logic and empiricism, but no-one apart from the most annoying of existentialists have a problem with it.

 

There is also room for abduction, which is the least sturdy of all, commonly known as inference to the best explanation.

• There are fox's paw treads here
• No other animal is known to leave fox's paw treads
• Therefore a fox went by recently

This requires super-empirical reasoning so it clashes slightly with a strict realist worldview, but that's not massively important.

 

These are all types of proofs, they aren't all logical. Mathematics only tolerates deductive proofs, but science uses all three (as do legal systems).

 

What you're looking for, however, is a counter-example to the statement "logic is not based experience (at all)", by finding at least one instance of logic being based on experience.