Why Darwin Matters_ The Case Against Intelligent Design - Michael Shermer [7]
But life is far more complex than a watch—so the design inference is even stronger!
There cannot be design without a designer; contrivance without a contriver. . . . The marks of design are too strong to be got over. Design must have had a designer. That designer must have been a person. That person is GOD.8
For longer than we have had the theory of evolution, we have had theologians arguing for Intelligent Design.
From Natural Theology to Natural Selection
After abandoning medical studies at Edinburgh University, Charles Darwin entered the University of Cambridge to study theology with the goal of becoming a Church of England cleric. Natural theology provided him with a socially acceptable excuse to study natural history, his true passion. It also educated Darwin in the arguments on design popularized by Paley and others.9 His intimacy with their ideas was respectful, not combative. For example, in November 1859, the same month that the Origin of Species was published, Darwin wrote his friend John Lubbock, “I do not think I hardly ever admired a book more than Paley’s ‘Natural Theology.’ I could almost formerly have said it by heart.”10 Both Paley and Darwin addressed a problem in nature: the origin of the design of life. Paley’s answer was to posit a top-down designer—God. Darwin’s answer was to posit a bottom-up designer—natural selection. Natural theologians took this to mean that evolution was an attack on God, without giving much thought to what evolution is.
Ever since Darwin, much has been written about what, exactly, evolution is. Ernst Mayr, arguably the greatest evolutionary theorist since Darwin, offers a subtly technical definition: “evolution is change in the adaptation and in the diversity of populations of organisms.” He notes that evolution has a dual nature, a “ ‘vertical’ phenomenon of adaptive change,” which describes how a species responds to its environment over time, and a “ ‘horizontal’ phenomenon of populations, incipient species, and new species,” which describes adaptations that break through the genetic divide.11 And I’ll never forget Mayr’s definition of a species, because I had to memorize it in my first course on evolutionary biology: “A species is a group of actually or potentially interbreeding natural populations reproductively isolated from other such populations.”12
Mayr outlines five general tenets of evolutionary theory that have been discovered in the years since Darwin published his revolutionary book:
1. Evolution: Organisms change through time. Both the fossil record of life’s history and nature today document and reveal this change.
2. Descent with modification: Evolution proceeds through the branching of common descent. As every parent and child knows, offspring are similar to but not exact replicas of their parents, producing the necessary variation that allows adaptation to the ever-changing environment.
3. Gradualism: All this change is slow, steady, and stately. Given enough time, small changes within a species can accumulate into large changes that create new species; that is, macroevolution is the cumulative effect of microevolution.
4. Multiplication: Evolution does not just produce new species; it produces an increasing number of new species.
And, of course,
5. Natural selection: Evolutionary change is not haphazard and random; it follows a selective process. Codiscovered by Darwin and the naturalist Alfred Russel Wallace, natural selection operates under five rules:
A. Populations tend to increase indefinitely in a geometric ratio: 2, 4, 8, 16, 32,