"Of all the gin joints in all the towns in all the world, she walks into mine."
As every film buff knows, that's what Humphrey Bogart glumly says in Casablanca, after his ex-lover (Ingrid Bergman) shows up at his Rick's Café Americaine. Bogart's Rick Blaine is of course justified in his astonishment - it certainly looks like a rather uncanny coincidence. However, most of us in the audience plainly realize that had Bergman chosen another joint, or another town, we'd simply be watching a different movie. In other words, if you are the main character in a movie, chances are you are part of an unusually interesting story: that's a so-called "observation selection" effect.
For reasons that I can't comprehend, however, this basic logic seems to escape a lot of fairly intelligent people, the most recent entrants on the list being astronomer Guillermo Gonzalez and philosopher Jay Richards. Their recently released book "The Privileged Planet" (TPP), argues not only that Earth is uniquely endowed for life forms just like us to appear (an old idea), but that our planet is also just right for those life forms to develop the scientific method, and to apply it to discover the fundamental Laws of the Universe. The series of coincidences behind these simple observations is so amazing, they say, that just a Cosmic Screen-writer could have come up with it.
Predictably, the book (and its spin-off documentary) is being hailed by Intelligent Design advocates as the best thing since, well, their last book and spin-off documentary. The National Review Online, which when ID is concerned seems to quickly shed any semblance of critical sense and journalistic standards, hosts a raving review, complete with tabloid-style bullet points and claims of (post-)Copernican Revolutions. I think all these apologists should be more cautious, as Gonzalez's and Richards' thesis seems to raise more problems for ID than it solves.
To be clear, I do not intend here to review the book or directly address its specific arguments. First of all, I am no astronomer, physicist or philosopher (and unlike many prominent ID advocates, I am loathe to blather about things I do not know enough about). Furthermore, some of these ideas, especially those related to the first part of the argument (the fine-tuned Earth and Universe) have already been addressed in many extensive discussions of TPP's philosophical granddad, the Anthropic Principle, in its Strong and Final iterations (a good starting point about the AP is Nick Bostrom's web site, altough several of its links seem to be broken). Finally, there are already some critiques of the Privileged Planet hypothesis circulating on the web (such as Kyler Kuehn's, summarized in this Powerpoint presentation), which I am sure will soon be developed more formally and published, now that the book is out.
I want to talk instead about the implications of TPP for ID advocacy in general. The thing that truly puzzles me the most is that the argument for the Earth's suitability for discovery goes smack against much of the ID rhetoric against "naturalistic" science. "Challenging the reigning ideology of materialistic naturalism" (as the jacket of Dembski's "Mere Creation" promises) has been one of the fundamental principles of ID since its founding. From philosopher Plantinga to ID's legal-eagle Beckwith, ID has consistently attacked science's methodological naturalism (the use of empirical evidence about natural causes to explain natural phenomena) as a front for, or even the cause of, philosophical naturalism (the metaphysical claim that natural causes are all there is) .
Methodological naturalism and the scientific method developed and flourished because they proved much more successful at interpreting natural phenomena than the alternative approaches, leading to all the amazing discoveries Gonzalez and Richards are so justifiably enthused by. In other words, the scientific method that TPP claims the intelligent inhabitants of a purposefully designed Earth were meant to ultimately develop and so spectacularly apply, is the result of the application of methodological naturalism. Without methodological naturalism, there would have been no science as we know it, and very arguably no Privileged Planet hypothesis.
So, is the scientific method good or bad? If it is bad, why has the Designer designed the Universe to fool us into using it? If naturalistic science is a mistake, and its accomplishments mostly illusory, the supposed Earth's "privilege" would in fact just be a big joke, on us. On the other hand, if the scientific method is good and useful, and was even pre-ordained by the Designer, why should we drop it now in favor of non-naturalistic ID "theory"?
Perhaps, one could say, it was also pre-ordained that scientific naturalism would run its course, and be replaced at this historical juncture by non-naturalistic ID, so that we could discern the Grand Plan. That sounds rather expedient, of course, but even taking it at face value, if the goal was for us to discover a Grand Plan, what better way to do that than an Aristotelian Universe of which the Earth is the proud geometrical center? Why the charade?
ID advocates usually dodge this kind of questions by quickly declaring that the intentions of the Designer are outside the realm of investigation, and gladly drop the subject. But this excuse would certainly not cut it in this case, since TPP itself is, strictly speaking, one long argument about the intentions of the Designer!
Finally, there is possibly a strategic issue at play here as well. ID advocates have long insisted that ID is not inherently religious because the Intelligence it purports to be capable of detecting could be a naturalistic one (eg, aliens). This would supposedly allow ID to leapfrog over the many constitutional hurdles against the teaching of religion in schools. However, any hypothesis about Planetary and/or Universal Destiny clearly makes this position untenable - this Designer can only be (a) God. It seems to me that, should ID fully and officially embrace TPP's thesis, its Establishment Clause strategy goes out the window, and with it its only chance to mold young minds, before their critical sense develops.
That's a problem, but as Bogart would say, "everybody in Casablanca has problems".