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0 pointsasdff6y ago0 comments

But they are looking for it. Science demands evidence for your claims. If x could be due to a, but also b, c, d, maybe e, you can't say x = a until you've proved that x ≠ b, c, d, e.

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jf-6y ago

The fastest way isn’t to eliminate the other possibilities, it’s to find a unique test for a that can’t be met by any of the others. Bear in mind that your list of alternative causes may be very long and each require large amounts of work to eliminate.

I too find it strange that multiple landers have been sent to mars since Viking, ostensibly looking for evidence of present or past life, and have yet have carried no tests for it. I find the best way to find something is to look for it.

ianai6y ago

The authors suggest testing for chiraliry in an LR test. Life creates certain “handed” organic molecules while purely chemical reactions do not. They said there’s already designs for flight ready tests. NASA just needs to include it in a mars mission. But they have no plans to do so.

This significantly increased my frustration with NASA.

drdeca6y ago

I thought life on earth favoring a particular chirality was supposed to be primarily because of like common ancestors and stuff. If you flipped the chiralities of everything, would stuff no longer work? Or, I guess really my question is, would it be nearly impossible for life on another planet to use the opposite chirality instead?

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bufferoverflow6y ago

Life on our planet does. Doesn't mean that's the case everywhere else. Or even anywhere else, for that matter.

read_if_gay_6y ago

Conversely you can't say x != a until you've proven x = b or c, d, e. Which is GP's point if I understood correctly.

rzzzt6y ago

"However improbable", Sherlock Holmes is often brought up in cases like this...

cgriswald6y ago

That quote always rubs me the wrong way. To reach certainty through deduction you need a closed domain. Assume Holmes is 100% correct about the information he has, and he has three suspects, two of whom he ruled out. Does that mean the third did the deed? No. There may be information Holmes does not have and there is really no way for Holmes to know he does not have that information.

rzzzt6y ago

Holmes does appear to be operating under the closed-world assumption: https://en.wikipedia.org/wiki/Closed-world_assumption

stan_rogers6y ago

That's contingent on eliminating the impossible.

cameron_b6y ago

the scope of which begs a complete understanding of the possible

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