Intelligent design

Intelligent design (ID) is a pseudoscientific argument for the existence of God, promoted by its supporters as a scientific, evidence-based explanation for how life began. It is a version of creationism that lacks empirical support, offers no testable or tenable hypotheses, and is therefore not considered science.

The idea rests on two main claims against evolution: irreducible complexity and specified complexity. Proponents argue that certain biological and informational features are too complex to have arisen through natural selection. However, detailed scientific examination has refuted these claims, and peer-reviewed research has published evolutionary explanations for the very features ID proponents said were impossible.

The leading advocates of intelligent design are connected to the Discovery Institute, a Christian, politically conservative think tank based in the United States. The movement seeks to challenge the methodological naturalism that underlies modern science. As a positive argument against evolution, ID draws an analogy between natural systems and human-made artifacts—a version of the theological argument from design for God’s existence. ID proponents then conclude that complex features, as they define them, are evidence of a designer. Critics point out that this reasoning relies on a false dichotomy: assuming that evidence against evolution automatically counts as evidence for design.

The phrase “intelligent design” had appeared earlier in theological discussions about the argument from design, but it was first used in its current sense as a substitute for “creationism” in the 1989 textbook *Of Pandas and People*, intended for high school biology classes. This change came after the 1987 U.S. Supreme Court case *Edwards v. Aguillard*, which ruled that “creation science” is not science and that teaching it in public school biology classes violates the Establishment Clause. Following that decision, all mentions of “creation science” in the textbook were directly replaced with “intelligent design,” and “creation scientists” became “design proponents.”

From the mid-1990s onward, the intelligent design movement, backed by the Discovery Institute, pushed for ID to be included in public school biology curricula. This led to the 2005 *Kitzmiller v. Dover Area School District* trial, which ruled that intelligent design is not science, that it “cannot uncouple itself from its creationist, and thus religious, antecedents,” and that promoting it in public schools violates the Establishment Clause of the First Amendment.

The argument from design has a long history. Thomas Aquinas used it in his fifth proof of God’s existence, and in 1802 William Paley’s *Natural Theology* presented the watchmaker analogy, arguing that just as a watch implies a designer, the complexity and adaptation in nature must also be designed. Paley concluded that the perfection and diversity of these designs point to an omnipotent designer, specifically the Christian god. Like creation science, intelligent design centers on Paley’s religious argument, but while Paley’s natural theology allowed for deistic design through God-given laws, ID seeks scientific confirmation of repeated, supposedly miraculous interventions in life’s history. Creation science prefigured ID’s irreducible complexity arguments, even using the bacterial flagellum as an example. In the U.S., attempts to introduce creation science into schools were struck down by courts as religious in nature, so it cannot be taught in public school science classes. Intelligent design presents itself as science and shares many arguments with creation science, but avoids literal biblical references like the flood story or using Bible verses to estimate Earth’s age.

Philosopher Barbara Forrest traces the start of the intelligent design movement to 1984, with the book *The Mystery of Life’s Origin: Reassessing Current Theories*, co-written by creationist and chemist Charles B. Thaxton and two others, published by Jon A. Buell’s Foundation for Thought and Ethics. In March 1986, ID proponent Stephen C. Meyer reviewed this book, discussing how information theory might suggest that DNA’s messages show “specified complexity” and must have been created by an intelligent agent. He also argued that science relies on “foundational assumptions” of naturalism that are as much a matter of faith as those of “creation theory.” Later that year, Thaxton described his reasoning as a more sophisticated version of Paley’s argument from design. At a 1988 conference Thaxton organized called “Sources of Information Content in DNA,” he said that his intelligent cause was not necessarily the God of the Bible.