The notion that there was an intelligent designer who created absolutely everything from scratch and in accordance with a rational plan is the psychological precondition of the willingness to look for patterns that are hidden to the ordinary gaze. Unless we believe that there is a code to be deciphered, we are psychologically reluctant to devote hours of our life, let alone our life itself, to the pursuit of deciphering it. We think, "Oh well, it may be all meaningless garbage," and decline the challenge of explicating the possibly inexplicable.
In short, the belief, or illusion, if you will, that the world is the result of intelligent design has been the necessary condition for the construction of Western science, and it explains the otherwise mysterious fact that science, in any genuine sense of this world, arose only in countries that were part of Christendom.
Intelligent design, in other words, was a constructive illusion. Who cares if an idea be true, if it has proven so fruitful in generating insights into the nature of things-a point that Immanuel Kant makes in his last great work, The Critique of Judgment, where he argues that in order to do science at all, scientists must begin by assuming that the universe has a far greater orderliness and intelligibility than these same scientists can ever hope to prove. Rather, they must begin by having a faith that the universe has been intelligently designed, in order to inspire them with the determination to discover this design, no matter how long it takes or however serious the obstacles to such a discovery prove to be. If, on the other hand, scientists began by assuming that the universe was simply a random, capricious, lawless hodge-podge of unconnected events, then who would ever be stirred to seek hidden patterns of regularity and veiled orders of significance?
If you cant find the time to read all of Harris article, at least read Cerbers excellent summary.