Constrained optimization is the art of compromise between conflicting objectives. This is what design is all about. To find fault with biological design - as Stephen Jay Gould regularly does - because it misses some idealized optimum is therefore gratuitous. Not knowing the objectives of the designer, Gould is in no position to say whether the designer has proposed a faulty compromise among those objectives.

Scientists rightly resist invoking the supernatural in scientific explanations for fear of committing a god-of-the-gaps fallacy (the fallacy of using God as a stop-gap for ignorance). Yet without some restriction on the use of chance, scientists are in danger of committing a logically equivalent fallacy-one we may call the “chance-of-the-gaps fallacy.” Chance, like God, can become a stop-gap for ignorance.

The fundamental claim of intelligent design is straightforward and easily intelligible: namely, there are natural systems that cannot be adequately explained in terms of undirected natural forces and that exhibit features which in any other circumstance we would attribute to intelligence.

Whenever explaining an event, we must choose from three competing modes of explanation. These are regularity, chance, and design... To attribute an event to design is to say that it cannot reasonably be referred to either regularity or chance.