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Comment by kvuj | Hacker News Reader

This feels like a thought exercise rather than an argument.

By your logic, it's impossible to prove that a car is driving at 60mph. There could be an error in the speedometer which makes it impossible to verify that said car is going at the speed. You can get asymptomatically close to being sure that you're driving at 60 mph but you can never be 100% sure.

This is useless and serves no purpose.

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That's not correct. You can prove a car is driving 60mph as soon as you measure it doing that. "proving a negative" is for statements like "There are no purple zebra". You can never prove this because there is always the possibility the purple zebra is somewhere you haven't looked yet. As soon as you find one the statement becomes falsified, but until then it always remains unresolved even if almost certainly true.

Linking back to the parent statement, it's hard to prove a program has no bugs when there is always the possibility the bug just hasn't been found yet. On the flip side it's easy to prove something does have bugs as soon as you find one.

You can prove there is no purple zebra on earth by actually surveying the population of zebras which is finite.

How do you know the one purple zebra wasn't just walking around in a way that meant they were always not where you were looking?

You can probabilistic say "it's extremely unlikely purple zebras exist" but you can never prove 100% they don't exist. And back to the real example, how can you prove there isn't a bug you just haven't found yet?

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