What is a proof?

[Kayenneh]

All men are mortal. (premise)
Socrates was a man. (premise)
Socrates was mortal. (conclusion)

This only works if you have all the parameters. One another classic example is this:

a) Swans are white birds.
b) Billy is a swan.
c) Therefore Billy is white.

If I tell you that Billy is actually black, you might disagree, since you've just deduced (based upon your experience that all swans you've seen are white) that I'm wrong. But then I show you this picture of Billy:



and prove to you that your deduction is faulty and Billy is indeed a black swan. Then you must change your assumptions to:

a) Swans are either black or white.
b) Billy is a swan.
c) Therefore Billy is black or white.

[Something completely different]

The reason for my avatar

read and learn:

http://en.wikipedia.org/wiki/G%C3%B6del%...s_theorems

[justin]

Second you have it ass backwards

I didn't

Inductive logic: weak entailment, less dependable, conclusion not guaranteed (don't confuse this to not to lead to right reasoning)

It is not weak, it is less affirmative than deductive logic, but it can bring new information

Deductive logic: strong entailment, guaranteed conclusion, most dependable.

yes, but it is actually not bringing any new information, it is just formulating existing facts (Premises)

My point is: even if the proof is using Inductive logic (and you don't have something better)
It should be considered as a proof

1:It is weak because it relies on probability, deductive does not.
and i just said that

2: uhh i never said it brought new information, though it can be used to give new info its just that the example you used has already been recorded information.

Your point: deductive logic is better than inductive logic so i do have something better, i just explained this. No the premise holds the proof the logic holds the reasoning.

---

The reason for my avatar

read and learn:

http://en.wikipedia.org/wiki/G%C3%B6del%...s_theorems

I wonder how his hair ended up like that? Natural? Cool as fuck if you ask me.

[Muslim Scholar]

and prove to you that your deduction is faulty and Billy is indeed a black swan. Then you must change your assumptions to:

a) Swans are either black or white.
b) Billy is a swan.
c) Therefore Billy is black or white.

You are correct
This proof fails because its premises is false (or not accurate)

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1:It is weak because it relies on probability, deductive does not.
and i just said that

I only disagree with the word "weak"
you should change it to probable because a probability of 0.001 is not equal to another of 0.999

[downbeatplumb]

I know what doesn't count as proof.

Anecdotal evidence and hearsay.

Or to put it another way, all religious books.

[Angrboda]

The reason for my avatar ... http://en.wikipedia.org/wiki/G%C3%B6del%...s_theorems

"Economist Oskar Morgenstern recounts that toward the end of his life Einstein confided that his 'own work no longer meant much, that he came to the Institute merely...to have the privilege of walking home with Gödel'." (Wikipedia: Kurt Godel)

[justin]

and prove to you that your deduction is faulty and Billy is indeed a black swan. Then you must change your assumptions to:

a) Swans are either black or white.
b) Billy is a swan.
c) Therefore Billy is black or white.

You are correct
This proof fails because its premises is false (or not accurate)

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1:It is weak because it relies on probability, deductive does not.
and i just said that

I only disagree with the word "weak"
you should change it to probable because a probability of 0.001 is not equal to another of 0.999

The fact that is probable and leaves the door open to evidence that could change the stance of truth. This is why it is called weak. Only in comparison to deductive because of a guaranteed conclusion. So use probable if want it works the same.

[Question Mark]

I seem to be a little late here, but as a historian, I was taught to appreciate the difference between proof and evidence as distinct but related concepts:

A proof is an evaluated meaning of what evidence tells one in relation to a question, which gives a sound basis towards or against a hypothesis or theory.
Evidence is an observation, material, or other clue that can be used to lend credence towards the validation or rejection of a hypothesis or theory if its meaning in regards to the question being asked can be deciphered properly.

For instance, a bullet casing found at the scene of a murder is evidence, but what it means in connection to the question at hand is proof, should the meaning be deciphered.

Proof in this context is what the meaning evidence gives to the observer when the evidence is evaluated in terms of the question being asked, and how it can apply to the proposed hypothesis or theory. It's taken from the mathematical model of proof where using known variables one can bring about a conclusion using a mathematical model, which admittedly I don't fully comprehend since I'm not terribly math savvy, but that's the gist of it. For instance don't ask me how Steven Hawking made 2+2 equal 5, because I don't know! >m<

[paulpablo]

This is not a debate, this thread is more educational
Give your thoughts, links, references and your beliefs

What are the types of proofs?
How to prove a statements?
How to disprove a statements?
What is impossible?

What are the basic premises that all agree on?

I don't know what everyone agrees on. It depends what you're trying to prove.

[Phish]

a good you are religious i can annoy you with this example: