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by nkrisc 558 days ago
> Citing laws of physics won't help you because any claim to have made a perpetual motion machine is implicitly claiming to be a proof by counterexample that one of those laws is wrong.

Citing the laws of physics in this case is the shorthand way to point the overwhelming number of proofs by example that the laws are correct.

1 comments

It doesn't matter how many examples you have for a law. A single genuine counterexample counts as a disproof.

If your law is all liquids flow off a ducks back. Water off a ducks back does not prove it. Acid off a ducks back disproves it. https://i.imgflip.com/7waajp.png

I don't think it is a matter of a shorthand. I think it is because humans have a tendency to express a strong opinion when they intend to express that a weaker opinion is strongly held. Citing laws of physics does not say "Your perpetual motion machine won't work" but rather "I am confident that your perpetual motion machine will be shown to not work".

Yes, that’s fair and I was sloppy with my phrasing. What I meant was that if you have 1,000 practical applications that function on the assumption the law is true and they behave as predicted, and then you have a single example that appears to disprove, then extraordinary claims require extraordinary evidence.

A single device, made in some garage, that appears to disprove it is simply not rigorous enough to prove anything and isn’t worth third party investigation until the creator has shown they’ve ruled out possible explanations.