Intelligent Design or “ID” contends that the universe and living things are best explained by an intelligent cause, not natural selection. The perspective has overlapping convictions with creationism, but the viewpoints are not identical. Adherents emphasize that ID is scientifically based, not religiously based, yet critics maintain that ID is religiously based, not scientifically based.
At the heart of the debate is a methodological controversy concerning whether non-testable supernatural events can be included in a scientific explanation.
The hub of the Intelligent Design movement is The Discovery Institute, which is a non-profit think tank located in Seattle, Washington, which advocates for ID in society. The Discovery Institute promotes anti-evolution curriculum and thought by means of its “wedge strategy,” which is their campaign to carve a niche in the public arena where anti-evolutionary science can be taught.
Many, but not all, ID proponents belong to the Christian religion.
Intelligent Design adherents, not surprisingly, postulate an Intelligent Designer. While most proponents are theists, it is argued that theism does not automatically follow from the argument. An alien intelligence, for instance, could account for design just as well. Some argue that proponents of SETI, that is the Search for Extraterrestrial Intelligence, hypothesize an intelligent alien agent. Nevertheless, most ID proponents believe that it is necessary for the designer to be non-physical and so ultimately conclude that theism is the best explanation.
Key Tenets of Intelligent Design
Irreducible complexity argues that certain biological systems are too complex to have evolved from less complete predecessors by means of natural selection. Irreducible complexity was coined by biochemist Michael Behe in his book, Darwin’s Black Box. Behe defined the term as “a single system which is composed of several well-matched interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning.”
Behe uses the analogy of a mousetrap to illustrate this concept. A mousetrap consists of several interacting pieces—the base, the catch, the spring and the hammer—all of which must be in place for the mousetrap to work. Removal of any one piece destroys the function of the mousetrap. Intelligent design advocates assert that natural selection could not create irreducibly complex systems, because the selectable function is present only when all parts are assembled.
Specified complexity is an argument offered by philosopher William Dembski, which posits that the existence of particular properties of living things is impossible without intelligent guidance. Dembski illustrates his contention this way: “A single letter of the alphabet is specified without being complex. A long sentence of random letters is complex without being specified. A Shakespearean sonnet is both complex and specified.”
The argument from a fine-tuned universe is more philosophical than scientific. It states that universal constants make the material world possible for which chance cannot account. Philosopher Alvin Plantinga articulates the common understanding for proponents of this view:
One reaction to these apparent enormous coincidences is to see them as substantiating the theistic claim that the Universe has been created by a personal God and as offering the material for a properly restrained theistic argument—hence the fine-tuning argument. It's as if there are a large number of dials that have to be tuned to within extremely narrow limits for life to be possible in our Universe. It is extremely unlikely that this should happen by chance, but much more likely that this should happen, if there is such a person as God (The Dawkins Confusion).
Astrophysicist Guillermo Gonzalez contends that if particular values were even faintly different, the universe would be radically different, making it impossible for certain features of the Universe, such as galaxies, to form. Adherents argue that an intelligent designer of life was needed to make sure that the necessary features were present to attain that particular result.
Many scientists have balked at responding to the fine-tuned universe argument, stating that it is philosophical not scientific and therefore cannot be tested.