The Gene: An Intimate History

by Siddhartha Mukherjee

General intelligence (g) originated as a statistical correlation between tests given under particular circumstances to particular individuals. It morphed into the notion of “general intelligence” because of a hypothesis concerning the nature of human knowledge acquisition. And it was codified into “IQ” to serve the particular exigencies of war. In a cultural sense, the definition of g was an exquisitely self-reinforcing phenomenon: those who possessed it, anointed as “intelligent” and given the arbitration of the quality, had every incentive in the world to propagate its definition. Richard Dawkins, the evolutionary biologist, once defined a meme as a cultural unit that spreads virally through societies by mutating, replicating, and being selected. We might imagine g as such a self-propagating unit. We might even call it a “selfish g.”