The Teleological Argument attempts to show that certain features of the world indicate that it is the fruit of intentional Divine design.
The most common form is the argument from biological design, paradigmatically presented by William Paley in his Watchmaker Argument. This argument has been refuted by the Theory of Evolution through natural selection.
A more modern teleological argument is the Fine Tuning Argument, which attempts to show that certain features of physics indicate our universe was designed to support life. This is the most serious current teleological argument, and will be handled here. It is closely related to the Anthropic Argument, so that will be discussed first.
There is another sort of teleological argument, a metaphysical argument that claims that design cannot arise naturally; even if it arises by natural means, it indicates a designer at the background. This line of thinking is addressed in the discussion the Argument from Reason.
Other issues other than design may indicate a Mind underlying the universe. The most relevant, perhaps, is the Argument from Cosmic Beauty.
The Anthropic Argument
The anthropic argument begins by noticing that if things were just slightly different, we wouldn't be here. Things seem to be just right for us to be here and keep on living. If temperatures rise or fall by a few degrees, we'll might very well perish. If our orbit was just slightly closer or further from the sun, we would likewise fry or freeze. Things are just right.
Consider the alternative. Let's say that our planet was, indeed, closer to the sun - so close, that all life will be burned away, yet we would still be there to see and discuss the ramifications. This will indicate that some special law of nature applies to humans - perhaps they are supernaturally cooling, unlike other life, perhaps an angel acts as a shield for the sun's heat, whatever. Such a state of affairs will clearly indicate that we are special in the grand scheme of things, and will indeed strongly indicate that Naturalism is false. But you can't have it both ways - if things are not well-suited for life then God exists (so I've just argued), yet if things are well-suited for life God exists too (the anthropic argument argues): that's just not very correct.
Of course conditions are such that they support our existence. This is not the issue, for otherwise we would not be existing to discuss it (this is the "weak anthropic principle"). The question is, rather, whether the world seems directed at supporting our existence. Just like all the cogs in a watch are directed towards keeping the dials moving in an orderly fashion. If humans do enjoy a privileged position in the universe, through special human-centric laws (the heat-repelling angels above) or through special location (such as the geocentric spheres in Artistotle's physics) then the anthropic argument would be plausible. But this is just not the situation - as far as we can tell, most features of the solar system, galaxy, and so on are totally unrelated to our existence, and are not directed at any particular goal (not us and not anything else); they just are.
The Fine Tuning Argument
In the late 20th century scientists have realized a strange fact about the way the equations of physics are built - the emergent physics is extremely sensitive to the choice of constants. If you change the constants even by a tiny bit, the world will look very very different - it will probably have no suns, no chemistry, and - therefore - no life. This is known as "fine tuning".
The similarity to the anthropic argument is striking - it seems the universe is "fine tuned" for life. Perhaps, then, all these other stars and so on are directed at supporting life, as they are what emerges from laws of nature that support life. Stars are needed to create heavy atoms, creating chemistry, and so on.
One problem with this argument is that it belittles god. God could have, supposedly, made the world Artistotelian. All this garbage - other stars, planets, the incomprehensible vastness of our universe - is utterly unnecessary to support life, or any other purpose. It is only necessary when God is limited to playing with the few dials modern physics allows in its choice of constants - and that is a weak god indeed.
Another problem is that the anthropic principle holds regardless of fine-tuning. Even if it would take fine-tuning not to support life, the fact that we live in a world that supports life is still not apparently necessary. God still chose just those constants that support life - he just had more choices. This raises the Argument from Contingency, the questions of why things are the way they are, but the evidential fine tuning of things becomes irrelevant.
The argument doesn't really address the scientific finding - it isn't that the universe supports life as a whole, but rather that physics only allows for life under certain very narrow choices of constants. It isn't clear why God would create a world with rules designed with this feature, and this is the key question raised by this finding. The Argument from Fine Tuning doesn't even begin to confront it. All it is, instead, is just another bad anthropic argument.
It isn't clear what is the physical significance of this finding. But whatever the consequence of it - it isn't god.
References and Notes
- There is some doubt whether this is even true. See, for example, Anthony Aguirre, PRD 64, 083508 (2001). For the purposes of this discussion, however, let us accept it as a fact.
See also http://www.philosophyofreligion.info/?page_id=24 http://plato.stanford.edu/entries/teleological-arguments/ http://www.carm.org/apologetics/teleological.htm http://www.leaderu.com/offices/billcraig/docs/teleo.html http://philosophy.tamu.edu/~gary/intro/paper.paley.html