THE BEST OF ALL POSSIBLE WORLDS

Nadler (Philosophy/Univ. of Wisconsin; Rembrandt’s Jews, 2003, etc.) recounts a major episode in the history of early modern philosophy.

For centuries, philosophers have worried about the so-called problem of evil. Why did God create a world in which evil acts, the cause of so much suffering, are commonplace? If God is “constantly and intimately causally involved in the world,” as Nadler puts it, then why does he allow sin? Though such questions seldom exercise us moderns—who have come to the conclusion that “the world God created does not seem to be a very just place”—they were of signal concern to thinkers of past generations, particularly those of a theological bent. Enter Leipzig-born Gottfried Wilhelm Leibniz, polymath mathematician and philosopher, who, Nadler reveals, was also a secret agent working behind the scenes at the court of King Louis XIV on behalf of the city-state of Mainz, Germany, to settle an ever more tendentious rivalry between France and Holland. Leibniz acquitted himself well enough in that job, but he found himself more wrapped up in conversations with newfound friends Antoine Arnauld and Nicolas Malebranche, who were absorbed in that timely problem of evil. The Lutheran but ecumenically minded Leibniz found lively interlocutors in the Catholic Malebranche and the Cartesian Arnauld, and they argued for years—all living to a very old age, perhaps kept going by the discussion. Nadler gives a lucid, graceful account of their back-and-forth, adding an elegant gloss of his own with unsettling touches, as when he observes, “Even God cannot bring it about that the world is governed by the most simple laws and that everyone is happy.”

An exemplary entry in the history of ideas.