All organisms vary, and it's just folk knowledge. You just have to look around a room of people, and everybody knows that it's true. Darwin didn't know the mechanism of heredity, but you don't have to. You just need to know the fact of it.

Evolution is an inference from thousands of independent sources, the only conceptual structure that can make unified sense of all this disparate information.

Creationist critics often charge that evolution cannot be tested, and therefore cannot be viewed as a properly scientific subject at all. This claim is rhetorical nonsense.

As we discern a fine line between crank and genius, so also (and unfortunately) we must acknowledge an equally graded trajectory from crank to demagogue. When people learn no tools of judgment and merely follow their hopes, the seeds of political manipulation are sown.

Nothing is more dangerous than a dogmatic worldview - nothing more constraining, more blinding to innovation, more destructive of openness to novelty.

A man does not attain the status of Galileo merely because he is persecuted; he must also be right.

The board transported its jurisdiction to a never-never land where a Dorothy of the new millennium might exclaim: "They still call it Kansas, but I don't think we're in the real world anymore."