Posted on 03/05/2011 5:51:25 AM PST by SonOfDarkSkies
I know where I heard it first, Carl Sagan on Cosmos.
You owe me a keyboard. A little warning would have been appreciated, but coffee probably would still be dripping off my computer.
OMG it is a baby CREEPING TERROR! WE ALL GONNA DIE!
http://www.imdb.com/title/tt0057970/
A newlywed sheriff tries to stop a shambling monster that has emerged from a spaceship to eat people.
“This is a basic tenet in most jurisprudence. Extraordinary claims require extraordinary proof.”
Hmm. I was a trial lawyer for 25 years and never ran into this one. Civil trials require a preponderance of evidence. Criminal, beyond a reasonable doubt.
If you had this other standard, then whoever gets to define what’s extraordinary wins almost every time.
“I know where I heard it first, Carl Sagan on Cosmos.”
Yes. Of course he would say it. He was much more about polemics than science. It’s always good if you’re the guy who gets to decide what is ordinary and what is extraordinary. Then you’re the one who decides most scientific disputes.
Well, he used it specifically about alien abductions and UFO’s and in that case he was right.
And it come from the planet Krypton.
The closest you can get to that in statistics is a strong Bayesian prior agin’ the proposition, which itself has to be justified as more than someone’s whim. And actual evidence in favor of the proposition quickly overwhelms even strong priors to the contrary.
The evidence is either consistent with the hypothesis, inconclusive, or it disproves the hypothesis, regardless of the biases of the reviewer.
Personally, I don’t think there is ET life—at least not complex life. But that doesn’t change what evidence supports and doesn’t support the hypothesis.
I don't know about any "meme." Everything I said is based on experience as a scientist. I have no particular emotional attachment one way or the other to the idea of life existing other than on the Earth, and I think that life has probably evolved elsewhere. That has no bearing on the fact that I am highly skeptical of the claim.
In making the claim that extraterrestrial life has been found, one must absolutely and rigidly disprove the null hypotheses, which are:
--The structures observed are artifacts contained within the sample.
--The sample was contaminated.
It is simple to state these, but incredibly difficult to show them. If the structures are, in fact, microorganisms, then how can it be shown that they are of non-Earth origin? First of all, why they didn't burn up during the meteorite's plunge to Earth? How were they not destroyed by the cosmic radiation, intense cold, and vacuum that characterize space? Even if the structures are the remains of microorganisms, can one be absolutely certain that nothing could crawl inside the rock through microfractures? How can one know that the microtome used to slice the samples didn't drag something onto the pristine slice? Let's say that they are shown to be microorganisms, and their biology is unlike any we are familiar with--well, there are plenty of examples on Earth of organisms that live in extreme environments and have vastly different biologies than those we encounter on a daily basis. And so on.
To control against contamination, the analysis must be conducted in an environment where contamination is not possible--and it's hard to think of a suitable place on Earth. The only way I can see to sufficiently control against the possibility of contamination would be to examine a rock that has never been on Earth, using instrumentation built and operated remotely.
I should also point out that statistics, in this case, is completely irrelevant. In order to run a statistical analysis, you must have something to compare--when speaking of claiming that there are extraterrestrial organisms within a rock, exactly what are you going to compare? What are the appropriate statistical tests?
I don’t know why my search didn’t pick that up? Must have been a different alien lifeform?
I don’t disagree with anything you just wrote. But nothing you would like to see is what I would call “extraordinary.” It’s just proving the case in a likely contamination-free way. The claim itself is not characterized as extraordinary. It’s just hard to prove in a rigorous manner.
I thought you were using the phrase in the Carl Sagan sense: “extraordinary claims require extraordinary proof,” which I have always regarded as a bogus concept allowing some self-designated folks to decide that hypotheses they don’t like require a different standard of proof than others they do like.
“Well, he used it specifically about alien abductions and UFO’s and in that case he was right.”
Not really. Why do the following two propositions require a different standard of proof:
“The Sears Tower is in Chicago.”
“Aliens abducted Jane Doe on Dec. 30 2001 and subjected her to bizarre probes.”
My personal belief is that 1 is likely true and 2 is likely not true. But they are both factual hypotheses subject to evidence that tends to increase or decrease the probability of their truth. Why is Sagan right that 2 requires me to accept only super-evidence on its behalf while I may accept just regular old evidence for 1?
I suspect it’s because, like me, he agreed with 1 and disagrees with 2 and because he finds people like Jane Doe annoying. In other words, he’s made up his mind and doesn’t want to argue about it. That’s fine—he doesn’t have to.
But posing his personal beliefs (supported by the consensus of all his friends who are also surely annoyed by white-trash alien believers like Jane Doe) as being important enough that their beliefs comprise the dividing line between regular old proof and super-proof strikes me as very similar to the polemics of the Grand Alchemists of the global warming debate—”We’ve made up our minds. Just stop denying AGW and get on board.”
I’ve always regarded the “extraordinary claims require extraordinary proof” saw to be a polemical, not a scientific, point. And it is almost always used polemically. The wand has been waved. I win. I’m a scientist. Now stop arguing!
What I mean by “extraordinary proof” may or may not have any relation to what Carl Sagan meant by it. I didn’t really follow Sagan, so I am not very familiar with him. I just mean that the burden of proof is greater than that encountered by most scientists in their normal work, therefore it is extraordinary.
Note: this topic is from 3/05/2011. Thanks SonOfDarkSkies.
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I got one of them in my colon. Signing off now, I gotta shiite.
Earth life is based on DNA. DNA is software, which tells a ribosome (via RNA) what sequence of amino acids to assemble to create a particular protein. I would be as surprised to find an alien life form based on our version of DNA, as I would to find an alien computer that ran Windows.
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