My unfortunate habit is to zero in explicitly on the negatives of anything I examine, while leaving the positives implicit. In order to avoid this vice, I'll say here at the start that I enjoyed the film and got a lot out of it. Most of the people I talked to enjoyed it too. One notable exception being the friend I sat next to; she thought it boring (she thrives on conflict, so perhaps she didn't find enough of it to hold her attention).
Please note that this review is not intended to be comprehensive, but simply to touch on the elements of the film that most struck me. If you're looking for a more comprehensive review, Denyse O'Leary at Post-Darwinist has written an entertaining and very thorough one:
I've only seen the film once, and alas don't have Denyse's gift for remembering detail.
The event flowed smoothly with the exception of a small glitch in valet parking that recommended a half-hour delay. The Baird Auditorium, I would estimate, was not quite half full, not more than 300 in the audience. Bruce Chapman, President of the Discovery Institute, introduced those around the room involved in the film's production before introducing the film itself. Following the film, the authors of the book on which the film was based, Guillermo Gonzalez and Jay Richards, took the stage to answer questions. Afterward there was a top-flight reception in the Museum's splendid Hall of Gems.
The film begins with a discussion of the "Copernican Principle" and the "Principle of Mediocrity" into which it has hypertrophied and metastasized. Recall that Copernicus demoted the Earth from its traditional placement at the center of the universe in favor of the Sun. Many people take the historical essence of this "revolution" to be the increasing realization of the unexceptionalness or "mediocrity" of us and our planet. This "Principle of Mediocrity" became a fundamental principle in many minds when Edwin Hubble discovered that the universe expands unimaginable distances beyond our galaxy; and our galaxy turns out to be an unextraordinary example of the billions and billions of galaxies scattered across the cosmos. With the discovery of this second data point ("and gee whiz! two points define a line and look where it goes!"), the idea that scientific "progress" inevitably increases the Earth's marginalization became cemented in the progressive mindset.
The next section enumerated the many unusual circumstances that make a habitable planet like our own such a rarity. To introduce the "measurability"1 of our planet, a brief, semi-biographical look at the northern Indian solar eclipse that gave Gonzalez the idea. "Measurability" is his term for the suitability of a planet for its inhabitants to observe and discover the universe near and far.
The film highlights the necessary link between a planet's habitability and measurability. For example, a habitable planet can't form in a nebula2 because of the high incidence of dangerous supernovae; likewise a nebula would also obscure our view of all but the very nearest stars. A large moon stabilises a planet's moderate axial tilt to allow the seasons that are necessary for life and in Earth's case the fact that the Moon's apparent size is so incredibly coincident with the Sun's allows perfect eclipses.3 These eclipses have been key to so many scientific experiments essential to understanding the laws of the universe.
The film next turns to more universal rarities, such as the fine-tuning of physical constants that make possible astronomical bodies, chemical bonds, etc. that are prerequisite to a universe that permits life.
The film ends by summarizing its results and dispelling the false generatization of the "Copernican Principle" to the mythical "Principle of Mediocrity" that dominates modern thinking. Copernicus only showed the Earth isn't the center of the universe; Hubble only showed the universe is much larger than we had dreamed. The Earth is special for combining those rare characteristics that make it not only highly hospitable to life, but also highly conducive to discovering the universe and the fact that it is not an accident.
Far from being "unscientific," this discovery continues the quest of scientists of yore, such as Copernicus, Kepler, and Newton, who turned to science seeking the purpose and design placed in the universe by its Creator. (Scandalous, isn't it?)
My view is that the production was very professional. The computer graphics were crisp and colorful. Visually the film fares well in the obvious comparison with Carl Sagan's Cosmos (though the soundtrack wasn't as memorable). I particularly appreciated the clever transitions between shots, which often played off visual similarities. One such transition (ripples from a water-drop) was belabored to the point of cloying.
For the most part, the reasoning and explanation of the argument was superb and well-paced.
The narrator was well chosen: a skilled speaker with a wonderful voice. Initially, his grand English accent struck me as lurking just this side of comically grandiose, but I gradually grew accustomed to its timbre.
The "talking heads" were well integrated into the narrative. Robin Collins, philosopher from Messiah College who appeared in the latter half, was well spoken but has a look in his eyes that could plausibly come from a diet of locusts and wild honey.
I got to ask the first question6, which was definitely the most critical asked. The issue was the necessity of the coincidence between habitability and "measurability." It seems to me that (as many of the ID arguments with respect to evolution observe) a factor can express a message to the extent that it is not deterministically caused. So, for example, the fact that the physical forces between ink and paper don't completely determine the placement of ink on a page allows written communication. For this reason it seems to me that the Earth would better express a message from its "Designer"—it would be a more privileged or special planet—if the correlation between habitability and "measurability" were unnecessary, gratuitous. (The question that was the excuse for my comments died on my lips. I wanted to know whether the authors had come across any measurability characteristics that weren't necessary for habitability.)
I am unable to capture the explosion of words and ideas that flew back at me, but the response (here and talking to Jay Richards at the reception) boils down to (in my words) this link's showing we live in a "privileged universe."
Stuff about Numbers
The idea of universal priviledge brings us to my other difficulty with the film's argument. As even scientists inimical to the Discovery Institute admit7, the physical constants that govern the forces of the universe seem to be "fine tuned" for life, by which they rather inexplicably fall into the narrow range of values that allows the wonderful habitability of the world we live in.
My argument against the "narrow" conclusion is rather abstract and probably poorly formulated. For this reason, unless you're a geek compulsively fixated on these questions like me, you may want to skip down to the conclusion.
Basically it comes down to the question: what is the basis of comparison for saying the range of values is "narrow"?
Notice that saying something is near or far (that the distance is small or large) requires an at-least implicit comparison to another length, such as one's stride. Without a basis for comparison, using "narrow" or "wide" as a descriptor is completely arbitrary. In the abstract, any given parameter can vary from infinity down to zero: what range of values isn't narrow compared to infinity?
Conceivably, one could use the magnitude of the parameter itself as the basis of comparison. But this procedure also seems rather arbitrary: why should a five-percent variation, say, in a small-valued parameter mean a smaller absolute variation (e.g., variation of 5 for a value of 100) than in a large-valued parameter (e.g., variation of 50 for a value of 1000).
Behind these difficulties in mathematical scaling, there lurks a more fundamental problem: what does it mean to vary universal constants physically? We can talk all day about fiddling with abstract values, but mathematical and physical difficulties are not necessarily connected. For example, the difficulty of removing ten pounds from a living one-ton elephant is much greater than removing 100 pounds from a one-ton pile of sand.
Honestly I don't have a clue of even how to address the meaning of varying universal constants, but I suspect the route runs through fields more fundamental than physics.
Privileged Planet is well thought-out, well written, and well produced. My abstruse difficulties do not damage the film's overall thesis, and certainly not its intellectual and historical importance. The controversy around it alone merits its inclusion on your must-see list, but apart from sensational interest, the ideas it presents deserve serious consideration.
1. I think the term misleading: a planet's "measurability" sounds like the planet itself is being measured. May I humbly suggest some less awkward alternatives? "Vision," "sightedness," "discernment," "unobstructedness" all seem more expressive of the concept.
2. Cf. Douglas Adams, Life, the Universe, and Everything.
3. The historical contingency of scientific discovery keeps the measurability part of this argument from being quite as strong as the habitability part.
4. Cf. Kevin Smith, Jay and Silent Bob Strike Back (2001).
5. General "Buck" Turgidson in Stanley Kubrick's Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964).
6. Of course, here more clearly formulated.
7. Indeed these naturalistic scientists have devised various "anthropic principles" to account for it without recourse to that frumpy "God hypothesis."