it comes in pints?

I have no title for this post because it's too long and I'm wasted

[UPDATE: I corrected the honorific for Dr. Bostrom; that should have occurred to me last night]

Our buddy Bings linked to an article by Nick Bostrom. I mocked a bit of it below, probably unfairly, but the phrase amused me.

And this may have gotten overly long and rambling, so apologies in advance if it's not up to my usual super-journalistic-fiskatory standards. Which I doubt it would be even if I actually had such standards. My only defense is that Dr. Bostrom's article is also overly long and rambling. And I'm drinking.

It's not so much that Dr. Bostrom is wrong in his analysis, though I think it's at best woefully incomplete. He just seems terribly overwrought about the possible implications of finding out that life might exist outside our small, fever-ridden orb. As I mentioned in Mr. B's post, it reminded me of Bertrand Russell's depression over entropy, or this guy's rather ridiculous views on Darwinian evolution.

I haven't the time nor, realistically, the expertise in the appropriate fields to a thorough job on it but I'm well enough informed, I think, to point out some rather large flaws.

Such a discovery would be of tremendous scientific significance. What could be more fascinating than discovering life that had evolved entirely independently of life here on Earth?

What indeed? It would be great to learn that life on Earth is not just some weird, cosmic accident.

But I hope that our Mars probes discover nothing. It would be good news if we find Mars to be sterile. Dead rocks and lifeless sands would lift my spirit.

I think that attitude is just sad myself, but his argument is, I think, very poorly fashioned.

Before the actual arguments, though, he throws in a little bit of utter foolishness:

Conversely, if we discovered traces of some simple, extinct life-form--some bacteria, some algae--it would be bad news. If we found fossils of something more advanced, perhaps something that looked like the remnants of a trilobite or even the skeleton of a small mammal, it would be very bad news.

Yeah, it would mean the damned trilobites beat us in the Space Race.

Okay, in fairness, I assume he knows that anything we might find would not actually be related to any critters on Earth. The simplest might closely resemble bacteria or algae but certainly there would be no trilobites or mammals. For that matter, I don't even know if they could be reasonably referred to as plants or animals (that would make an interesting philosophical discussion, though, but from here on I'm going to drop the "resembling" part and just call them by the earthly analogs). He's just trying to make a point about finding multicellular, even large, complex species.

The more complex the life-form we found, the more depressing the news would be. I would find it interesting, certainly--but a bad omen for the future of the human race.

[sigh] Yeah, well, I think this passage is really silly and not just for the "bad omen" part. The likelihood of finding fossils of large, complex creatures is zero (well, perhaps not exactly zero, but close enough for Rock 'n' Roll). On Earth, bacteria don't just outnumber, they outweigh eukaryotes. The fact that visits have not yet turned up evidence of even bacteria pretty well guarantees that no large critters ever existed. And that's not even considering the likelihood that whatever surface water Mars may have once had dried up or froze into permafrost before the emergence of larger metazoan types (600 million years ago on Earth, after three billion years of bacteria and blue-green algae).

Now, that's not to say we won't eventually find evidence of bacteria, even primitive eukaryotes, perhaps even living bacteria in permafrost or some other hidey-holes (they can be pretty tenacious). But this part is really just a sidetrack to the meat of the article.

How do I arrive at this conclusion? I begin by reflecting on a well-known fact.

Actually, two well known facts. He goes into a fair amount of detail, but these two facts really boil down to:

1) We haven't had any visitors from space and, despite the efforts of the Search for Extra-Terrestrial Intelligence (SETI), we haven't detected any signals from space, and

2) There are about 100 billion stars in our galaxy, and about 100 billion galaxies, and if any of them had intelligent life, they would have already colonized the entire galaxy and maybe even the Universe.

From the first fact, he delves momentarily into the Fermi Paradox, about more of which later. Also, the SETI argument doesn't impress me too much. The night sky, far from being, as Dr. Bostrom puts it, "empty and silent", is awash in noise from the Cosmic Background Radiation to gamma rays. And among this noise, an intentional signal (and it would have to be intentional; those radio and TV signals we've been putting out for several decades are almost certainly unintelligible to alien civilizations. Especially the "Gong Show" and "The View") would be almost undetectable, much less recognizable, unless we had a dish antenna pointed directly at it. If there are any stay-at-home civilizations out there, I doubt we could actually detect them (this is not to say we should cut funding to SETI, it's a drop in the bucket and the potential payoff in knowledge is huge, but I just don't believe it will pan out even with millions of civilizations out there).

From the second fact, he concludes, almost certainly rightly, that there are many Earth-like planets out there capable of harboring life. Astronomers may quibble about the numbers (most stars may be binaries which have no planets, many may not form habitable planets, etc.), but bottom line is that there is a big ol' boatload of them even in our own galaxy.

From these two facts it follows that the evolutionary path to life-forms capable of space colonization leads through a "Great Filter," ...

Okay, this is what set me off. Phrases like this smack of pseudo-science and set my teeth on edge, which why I had some fun with it below. That's not fair to Dr. Bostrom and, on a few hours' reflection and a rereading, I realize that my first reaction was a bit harsh. Not that it affects my opinion of the article, but I'll try to tone it down a little.

... which can be thought of as a probability barrier... the filter consists of one or more evolutionary transitions or steps that must be traversed at great odds in order for an Earth-like planet to produce a civilization capable of exploring distant solar systems. You start with billions and billions of potential germination points for life, and you end up with a sum total of zero extraterrestrial civilizations that we can observe.

Okay, beyond the chosen phrase, he's not really too far off base here, but that "sum total of zero" is a problem. As mentioned, it may be only our inability to detect, or their inability to transmit, detectable signals.

Okay, long story short for tonight, because it's getting late and I need my beauty sleep (desperately! Just ask Julie and Emily). Dr. Bostrom's problem is that he assumes (1) that an advanced civilization would colonize the galaxy in a few million years if it were capable of doing so and that all advanced civilizations have that capability, so if we haven't been colonized already that must mean that other advanced civilizations don't exist, (2) that because other advanced civilizations don't exist, either we are the only ones that ever existed or all advanced civilizations must necessarily self-destruct, and (3) if we are not the only ones that ever existed, then the reason that other civilizations don't exist is that all advanced civilizations are doomed to destroy themselves, and so we must be doomed.

Cheery outlook, eh? Well, there are more problems with his article than I can deal with tonight so I hope to get a chance to deal with them tomorrow or over the weekend.

Posted by Ken S at May 1, 2008 09:02 PM | TrackBack (0) |