Re: File Hashing

On May 29, 10:12 am, "Johnny Jörgensen" <j...@xxxxxxxxx> wrote:
3) To everybody who answered that my first two questions were identical:
They're not - it depends on the answer.

No it doesn't. They're logically equivalent.

Suppose the answer to question 2 was "yes" - i.e. there can never be
two different files with the same hash value. That implies that if two
files have the same hash value, they can't be different, i.e. they are
identical. Hence the answer to question 1 would have to be "yes" as
well.

To put it in pure logic terms, if A is the predicate "X and Y have
identical hashes" and B is the predicate "X and Y are identical
files", your questions were:

1) A => B
2) !B => !A

I hope you can see how these are logically equivalent questions.

Jon
.

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