It's often been said that one cannot prove a negative. I take this bit of
conventional wisdom to mean that one cannot prove that some event did not
happen. While certainly true for *some* negative hypotheses I cannot see
where this axiom is universally applicable. Just about all proofs are
have some degree of certainty, some are more certain than others. For
example, one can prove that Thomas Jefferson existed, but since none of us
knew him personally we cannot be entirely certain that he isn't some
widely shared fictional character. In the area of physicis, for example,
one prove that gravity exists with a high degree of certainty, but there
is still the possibility of a miniscule amount of doubt (perhaps some
unseen, all-powerful joker moves the pencil when you drop it, and
maintains the orbits of celestial bodies to make it look like gravity).

We've all heard of the Noah's Ark fable. Believe it or not, some people
actaully think that it is true. If I were to prove that this story could
not have happened with as much certainty as say a proof that Jefferson
indeed existed, will I in fact have proven a negative? I'll be glad to
provide several such proofs of the falsity of the Noah's Ark thing on
request, but I hardly think I need to present them to a rational audience
to make my point.

It's often been said that one cannot prove
a negative. ..

We've all heard of the Noah's Ark fable. Believe it or not, some
people actaully think that it is true. If I were to prove that this
story could not have happened with as much certainty as say a proof
that Jefferson indeed existed, will I in fact have proven a negative?
I'll be glad to provide several such proofs of the falsity of the
Noah's Ark thing on request, but I hardly think I need to present
them to a rational audience to make my point.