In contrast to the assertive, mechanistic René Descartes, who did not dwell on history, reflective, retiring Blaise Pascal recognized the whimsy of the human past. He emphasized: But for a grain of sand—a kidney stone—Cromwell might have ravaged Europe; had Cleopatra’s nose been shorter (had she been less assertive and plainer), Antiquity would have taken another course. Contingencies of health and passion do indeed explain events. Without taking account of them, lives hang indecisively in a world of fantasy.
That limbo of the imagination is the nemesis of intellectual history, the domain for Silvan Schweber’s Einstein and Oppenheimer. As an enterprise, intellectual history is at once synchronic and diachronic. If the products of a mind are worth discussing at length, it is because of their transcendent value. The writings of Plato still speak to us directly, giving us pleasure and profit, even if we know nothing at all about...
