But our ways of learning about the world are strongly influenced by the social preconceptions and biased modes of thinking that each scientist must apply to any problem. The stereotype of a fully rational and objective scientific method, with individual scientists as logical (and interchangeable) robots, is self-serving mythology.

I strongly reject any conceptual scheme that places our options on a line, and holds that the only alternative to a pair of extreme positions lies somewhere between them. More fruitful perspectives often require that we step off the line to a site outside the dichotomy.

Precise adaptation, with each part finely honed to perform a definite function in an optimal way, can only lead to blind alleys, dead ends, and extinction.

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."

Transitional forms are generally lacking at the species level, but they are abundant between larger groups.

Change is more often a rapid transition between two stable states than a continuous transformation at slow and steady rates. . . .Change occurs in large leaps following a slow accumulation of stress that a system resists until it reaches the breaking point. Heat water, and it eventually boils. Oppress the workers more and more and bring on the revolution.

Recapitulation provided a convenient focus for the persuasive racism of white scientists; they looked to the activities of their own children for comparison with normal adult behavior in lower races.