Originally Posted by Roq
In a strict usage of the term, nothing can be a fact that depends on empirical evidence i.e. experience of the world, since you can't look in every cupboard to see if a unicorn is there (or not there)…. So proof (and fact), strictly speaking, only apply to a priori logical derivations from assumed axioms. That's restricted to mathematics and logic. Such as syllogisms:
Socrates is a man,
all men are mortal,
therefore Socrates is mortal.
That constitutes a fact, but only because the conclusion "Socrates is mortal" is already implied in the predicate axioms (i.e. the first two lines): *If* Socrates is a man *and if* all men are mortal then it logically has to be the case that Socrates is mortal.
But, none of that implies that the *evidence* for evolution isn't overwhelming.