Monday, August 08, 2005

Intelligent Design

When a Christian says that he believes that Jonah was swallowed by a big fish, you can assume that this is taken on faith. When a scientist says that she believes that modern species evolved from earlier species, you can assume that it has nothing to do with faith. A belief based on faith is one where there is little or no evidence. In science, evidence rules. The phrase "scientists believe..." can be read "scientists interpret evidence to suggest...".

When one espousing Intelligent Design says that Evolution is "just a theory", they say this to discredit Evolution. The implication is that scientific theories are ideas that can be easily overturned, unlike a scientific law. Indeed, scientific theories are subject to investigation, and can be overturned by the discovery of new evidence. But this is true for scientific laws as well. For example, Newton's Laws of Motion have been modified to take into account Einstein's General Relativity. The resulting relativistic laws of motion involve more complicated math than Newton's Laws, and under most circumstances result in answers that are the same for practical purposes. Still, engineers keep in mind where such short cuts won't work and use relativity where required. For example, the Global Positioning System (GPS) does not work without Relativity.

More than anything, the thing that really distinguishes a scientific law from a scientific theory is complexity. Laws tend to be very simple, often mathematical statements. The Law of Gravity states how gravity works. Objects have mass, and that masses attract each other, based on how much mass, and how far apart the things are. The Big Bang theory of the Universe is a complex theory. It involves modeling of stars, galaxies, black holes, and other phenomenon and explains how the Universe got to look the way it looks. It also makes predictions on what it will look like in the future.

Good theories make testable predictions. At the moment, the predictions of String Theory are not generally testable. Sure, String Theory makes predictions, but for all practical purposes, these predictions can not be tested. For example, at least one version of String Theory predicts that General Relativity will need to be altered somewhat. However, the Universe isn't currently old enough for photons emitted at the Big Bang to have yet behaved in a different way from what General Relativity predicts to be measured, even in principal. So, String Theory is not yet a good theory. Perhaps this will change, one day, as the theory is explored.

On the other hand, Intelligent Design does not make predictions of any kind, testable or otherwise. It suggests that some unknowable supernatural mechanism created life. It does not suggest how this was done, nor does it suggest how to gain insights into the process. Since Intelligent Design isn't subject to investigation, it isn't likely to produce any predictions, ever - unlike, String Theory. From a strictly scientific viewpoint, it is a dead end, and one can safely ignore it without missing anything important.

President Bush has suggested that Intelligent Design should be taught in school. Fine. However, it should not be labeled science. Intelligent Design is slightly warmed over Creationism, and is therefore religion. Science had a hand in the technology needed for airplanes and radios. Religion did not. The evidence suggests that the arguably most complicated machines - living creatures - have evolved in a process that is highly random and minimally directed. On the other hand, a simple radio is the result of an intelligent design.

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