hypnagogue said:
I apologize if I inadvertently put words in your mouth.
Oh, that's quite alright, it's probably just a semantic point to some extent.
Still, when it comes to using the AP in the context of explaining why it is that we find ourselves in a region of spacetime with finely tuned constants, I don't really see a knock-down problem. Perhaps asserting the AP here might not be useful for spurring scientific progress, but it certainly seems useful as an explanitory tool in the context of this scientific discussion.
I think many scientists view it as a "last resort", in the sense that it might explain the universe if we can find no further physical models to explain our "uniqueness". If we were to ever reach the point of last resort, however, scientific progress would have effectively ended. I don't know if that will ever happen.
To give an example of where it could be dangerous, consider it as an explanation for the flatness problems (that is, that the overall curvature of the universe appears to be so close to flat). One might be able to make an anthropic argument that says that such a condition is required in order for life to arise, but it doesn't really help things. If we were to settle on such a conclusion, we might be distracted from theories like inflation, which actually do have testable consequences (eventually, hopefully). Anthropic arguments really can't be verified by experiment, as I assume Smolin was arguing, so they make really dangerous "consensus" theories.
However, there may come a point at which the anthropic principle has
predictive power. That is, we might able to guess certain laws of physics by recognizing their necessity for our existence. Supposedly, this is what Fred Hoyle did when he predicted the excited state of carbon-12. We should again be careful, though, because it's hard to show that something is necessary for our existence and a lot of such predictions could be made that really aren't worth the effort to follow up.
There is the problem of how we can assert for sure that differing kinds of universes could not support intelligent life. This sort of thing would be difficult to show, I imagine, not the least due to the ambiguity of the words "intelligent" and "life," and the extent to which they could be stretched to include things that are drastically different from us. But if we restrict our inquiry to human life (eg "we human beings, with our various physical intricacies, exist in such a finely tuned universe because of all those that (might) exist, this is the only kind compatible with our specific physical makeup"), this seems to put the AP on much surer footing.
But is that really the right thing to consider? For purposes like Hoyle's, it certainly makes sense, but if we're going to consider theories like an "evolution" of universes, it would seem the more appropriate condition is that we be aware enough to ask these questions. This doesn't require human life, per se.