WRITING THE LIFE of a genius can make someone feel like a fool. After being absorbed by Isaac Newton for twenty years, his biographer Richard S. Westfall confessed that he understood him less well than before he started. The problem was that he and Newton had almost nothing in common. Westfall could not measure himself against such a genius, “a man not finally reducible to the criteria by which we comprehend our fellow beings.” Newton was “wholly other”; he did not think the way most people do, nor did he leave a model to follow. Moreover, he knew he was different. People seldom mattered to Newton, and often he treated them as if he wished they had never existed. But when he cared about something, he saw it with incredible, unshakable clarity: the world became transparent to him. Such clarity can seem more than human—at once inspiring and monstrous. Meanwhile the biographer plods along in the cloudy world where most of us live.

As a type of genius, Bobby Fischer had much in common with Newton. Both grew into their gifts in a brown study of intense isolation, while they played games with themselves; and they liked to imagine that they could make their own rules. Both were ruthlessly competitive, so convinced of their superiority that they were reluctant to acknowledge that anyone could rival them except by cheating. And therefore a shadow of fear hung over each of them, the threat of losing a game or making a mistake and being exposed as mortal. Both shrank from the public eye and from publication, though they expected to be idolized and often were. They subscribed alike to outlandish conspiracy theories, and succumbed to the illusion that their genius at chess or mathematics extended to fields like politics and religion, whose secrets only they could decode. No one really knew either of them. Occasionally patrons and friends stepped in to shelter them from harm, but even benefactors had to be on guard lest they be suspected of taking advantage or cashing in on the acquaintance. Late in life, despite their self-sufficiency, Newton and Fischer each became attached to an attractive young person, and each was crushed when the relationship fell apart. And ultimately, though others cared for them at times (and Fischer found a wife), they lived and died alone.

Endgame: Bobby Fischer’s Remarkable Rise and Fall—From America’s Brightest Prodigy to the Edge of Madness by Frank Brady // Crown Publishers, 402 pp., $25.99