I recently re-watched an old (April, 2006) Intelligent Design debate between Stephen Meyer and Peter Ward (you can find it online). The debate itself is not very balanced. Essentially Meyer gives a well-reasoned, thoughtful defense of ID for an hour and a half, and Ward interupts periodically to interject "It's not science". To racous applause, no less! It's not that Ward wasn't given equal speaking time, it's that he didn't really use his time to say much of anything with substance.

There is certainly a more convincing case to be made for evolutionary theory than Ward presents. What is really telling is the fact that he doesn't take ID seriously enough to think it worthy of any serious rebutal. Ward has serious academic credentials, but you would never know it from listening to the debate. He doesn't seem to think he needs to utilize them.

But what I really wanted to highlight is a clever argument which Meyer makes. He notes that Darwin and Charles Lyell (a geologist who had a major influence on Darwin) sought to explain their observations through "presently acting causes". The idea is that it is improper to invoke exotic causes to explain your observations. Observations should instead be explained by the forces which we see at work today.

Lyell was the first to explain geological formations by the accumulation, over long periods of time, of the processes of erosion which we observe today. Darwin sought to explain life the same way: as an accumulation of small, successive variations of the type observed by breeders (in fact, the very name "natural selection" was chosen because Darwin explicity compares it to artificial human selection).

Meyer takes this principle and extends it to information: we now know that living cells are the most complex machines on the planet, far outstripping anything that humans have designed and containing reams upon reams of digital information quite analogous to computer code. What, he asks, is the only presently acting cause of the sort of information that is found in computer programs? Intelligence! We observe that intelligence is capable of producing just exactly what we find in the cell. We observe that to get a complex new function out of an existing system, you must add code (information) via an intelligent agent. There is no evidence whatsoever that the near-limitless capacity for variation which Darwinian evolution requires is achievable through undirected processes. On those grounds we ought to prefer the presently acting cause, intelligent design, over exotic hypotheses about self-assembling molecules in the primordial soup, or the emergence of exquisite nanotechnology from random mutation.