String theory Zen
Now, I'm working out of a huge box -- Dan and I moved our dishes in one exactly like it -- full of muddled papers. Like I said, we haven't had the manpower to get to this stuff for months. So occasionally a magazine will show up that turns out not to have any of our books in it, and I just kind of poke through it quickly and see what interests me. This is how I ended up reading a more or less positive though somewhat snarky review of Leonard Susskind's The Cosmic Landscape in a January Times Book Review section. The book is about string theory, and is amusingly illustrated with a collage picture of stars, a measuring tape (?), and dental floss. I'm not saying I understand string theory, but wow, the artist sure doesn't. (And why should s/he, really.)
The review is written by Discover editor Corey Powell, who is reportedly a great guy and certainly knows plenty about science. One of us is wrong on something, though, because I found myself very puzzled by part of the piece. Powell writes:
Furthermore, it is inevitable that we would find ourselves in a universe well-suited to life, since life can arise only in those types of universes. This circular-sounding argument -- that the universe we inhabit is fine-tuned for human biology because otherwise we would not be here to see it -- is known as the Anthropic Principle and is reviled by many cosmologists as a piece of vacuous sophistry.Now, I think I'm confused. Is this the Anthropic Principle? (Wikipedia and her internet consorts are of little help on this one, I'm afraid.) Because I always thought the Anthropic Principle was something more like "the universe is this way because that's how humans need it to be to survive" -- a clearly absurd argument -- rather than "of course the universe is such that we can survive, else we would not have survived to ask about it." It seems more akin to the argument that humans have their specific traits (including, perhaps, the desire to believe in a designer!), not because they were made that way, but because the traits they have either were more adaptive than other traits, or came along with adaptive traits, or were sufficiently adaptive to remain. The inevitability, in other words, is in hindsight, not in design.
The pro-design argument hinging on the fact that "If gravity were slightly stronger than it is, for instance, stars would burn out quickly and collapse into black holes; if gravity were a touch weaker, stars would never have formed in the first place" (Powell) actually seems absurd to me for exactly the reason Powell is calling the Anthropic Principle -- and I hardly want to go on record saying I support the Anthropic Principle, so I'd like to get this cleared up! Is it, in fact, sophistry to say that the reason the universe operates on such principles that life on earth can exist is that, should any other circumstances have arisen, we'd hardly be any the wiser? Am I being insufficiently philosophically rigorous here? Am I unknowingly espousing a belief that amounts to intelligent design, or -- much less egregiously -- that demonstrates a vast ignorance of tricky cosmological theories?
I guess what I'm wondering is, if a universe can't support life, and no life evolves to notice, does it make a sound? And should it make a universe that can (and does) support life any more or less plausible to the life in question?