What is a proof?

[justin]

http://en.wikipedia.org/wiki/Critical_rationalism

proof doesnt exist, only constant reevaluation and reobservation.

Then what do you call this?

Deductive Proof

A deductive argument is one in which it is impossible for the premises to be true but the conclusion false. Thus, the conclusion follows necessarily from the premises and inferences. In this way, it is supposed to be a definitive proof of the truth of the claim (conclusion). Here is a classic example:

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

That's deductive logic. Not deductive proof.