An historical example of Design Theory
Doing Things With Words quotes a beautiful example from Carl Sagan:
Most curious is [Kepler's] view of the origin of the lunar craters, which make the moon, he says, "not dissimilar to the face of a boy disfigured by smallpox." He argued correctly that the craters are depressions rather than mounds. From his own observations he noted the ramparts surrounding many craters and the existence of central peaks. But he thought that their regular circular shape implied such a degree of order that only intelligent life could explain them. He did not realize that great rocks falling out of the sky would produce a local explosion, perfectly symmetric in all directions, that would carve out a circular cavity--the origin of the bulk of the craters on the moon and the other terrestrial planets. He deduced instead "the existence of some race rationally capable of constructing those hollows on the surface of the moon. This race must have many individuals, so that one group puts one hollow to use while another group constructs another hollow."
At least the Discovery Institute can take solace from the fact that they've now actually been compared to a scientist. It's far more flattering than they deserve, even though it was a scientist who was wrong…