Is Intelligent Design a Scientific Theory?
Thus we come to the crucial question: Is intelligent design a scientific theory? If by intelligent design, one means the Biblical account of God's creation of the world in six days, the answer is clearly no. Science is based on empirical observation rather than acceptance of divinely revealed truth.
However, most versions of intelligent design offered as alternatives to Darwinian evolution do not insist on the literal truth of the book of Genesis. Rather, they contend that gaps in evolutionary theory can only be plugged by the assumption that an intelligent agent has guided the development of life on Earth.
Some proponents of intelligent design do raise real objections to current understandings of Darwinian evolution. Based on my own reading of the intelligent design literature, it appears that its two strongest arguments point to the general absence of intermediate forms in the fossil record, and to unanswered questions about how certain new, complex patterns of animal bodies could have arisen through random mutation and natural selection.
Nonetheless, for two reasons, it appears that intelligent design is not a scientific theory.
The First Reason Intelligent Design Is Not a Scientific Theory: Conflating Uncertainty with Error
First, insofar as it offers itself as a critique of standard Darwinian evolution, intelligent design cherry-picks uncertainties at the edge of our knowledge, and asserts that these undermine our core understandings. But the fact that some phenomena remain unexplained by natural selection hardly shows that natural selection--which provides a powerful organizing principle for vast swaths of biological data--will not eventually provide the best account of these phenomena.
Consider an analogy. Our best current understanding of gravity remains mysterious because the most ambitious efforts to unify gravity with other forces in the universe--comprising so-called superstring theories or M-theory--have not been empirically tested. Yet that hardly calls into question the principal analytical tools of modern physics.
If the intelligent designers were to apply the same criticisms to physics that they apply to evolution, they would have to say that gravity, too, is "just a theory." However, the fact of Darwinian evolution is as real as the fact of gravity. To be sure, our understanding of each phenomenon is incomplete, but the scientific approach to plugging gaps in our knowledge is not to create a new-anti-theory that dismisses the underlying phenomenon.
The Second Reason Intelligent Design Is Not a Scientific Theory: It Isn't an Explanation
The second problem with intelligent design is even more fundamental: It does not actually explain anything.
Darwinian evolution by natural selection posits a mechanism that explains how species change over time: As environmental conditions change, individual members of a species with traits suited to the new environment survive and reproduce in greater numbers than those lacking the traits. And so, over time, and aided by randomly occurring occasionally adaptive mutations, the species evolves to adapt to the new conditions.
By contrast, what does it mean to say that species arise or change through "intelligent design?" Certainly the term connotes intervention by some intelligent agent. But are the intelligent agent's interventions themselves subject to the laws of the natural world, or are they supernatural?
Even if one is prepared to accept the possibility that science could, without sacrificing its essential premises, include accounts of supernatural phenomena, the concept of "intelligent design," standing alone, is simply a label, not an account.
To press the physics analogy, in classical mechanics, Newton's law of gravity--according to which the attraction between two bodies increases in proportion to the product of their masses and decreases in proportion to the square of their distance--was for many years viewed as problematic, because it described action at a distance. Scientists wondered: How did distant celestial bodies transmit their masses and positions to one another across space, such that they moved instantaneously in reaction?
To a substantial extent, Einstein's theory of general relativity solved the action-at-a-distance puzzle, but suppose that prior to Einstein someone had proposed that gravity worked through the operation of an "intelligent agent." It would have been a perfectly valid objection to this proposal that it isn't an explanation at all, but merely a restatement of the problem. For now, we must ask how the intelligent agent accomplishes action at a distance.
In both biology and physics, in other words, supernatural phenomena may be conceivable. But for an account of such phenomena to qualify as science, it must do more than simply posit an intervention from outside the ordinary natural order. It must also explain how the intervening agent interacts with the natural world. Otherwise, it is simply an article of faith rather than a scientific explanation.
FindLaw's Writ - Dorf: Why It's Unconstitutional to Teach "Intelligent Design" in the Public Schools, as an Alternative to Evolution
