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Theorem. There are no even prime numbers greater than 2. Proof. Assume n > 2, 2 divides n and n is prime. Therefore, 2 is a prime factor of n. But since every

Theorem. There are no even prime numbers greater than 2. Proof. Assume n > 2, 2 divides n and n is prime. Therefore, 2 is a prime factor of n. But since every prime number only has one prime factor, itself, then n = 2. But n = 2 contradicts n > 2. Therefore, no prime numbers greater than 2 exist. QED. - or - Claim. There is no beer in the fridge. Argument. I opened the fridge, there was no beer in the fridge. - or - p is a proposition. ~p is its negation. Take q = ~p. Proving p is the same as proving ~q. Seems to me you can most certainly prove "negatives".

thephyber 9y ago
> One can't prove a negative. Fine. One can't necessarily prove a negative. Only if you can prove the negation of the assertion can you "prove the negative". Now apply that logic to: <Musk> I can reduce the cost of boring by an order of magnitude. Can you prove that he can't? The gp was (over)simply stating that just because no other digging project has done what Musk claims to be able to do doesn't necessarily mean that Musk can't do it.