Drive

Drive: The Surprising Truth About What Motivates Us

In the spring of 1949, a psychologist named Harry Harlow set up a simple puzzle in a laboratory at the University of Wisconsin. The puzzle was a mechanical lock -- a hinged pin, a hook, and a hasp -- the kind of thing you might find on a garden shed door. Harlow gave the puzzle to a group of rhesus monkeys and walked away. He had not offered any food. He had not offered any praise. He had not promised anything at all. He just wanted to see what would happen.

What happened surprised him. The monkeys started playing with the puzzle. They prodded it, examined it, tugged at it with their fingers. And then, methodically, without any prompting, they began to solve it. Within a few days, the monkeys were taking the locks apart with fluid confidence, completing the sequence in under a minute. They looked, by any measure, like they were enjoying themselves.

This was not supposed to happen. The science of the day said that behavior was driven by two forces: biological drives like hunger and thirst, and learned rewards and punishments imposed from outside. You worked because you were hungry or because someone paid you. You stopped because you were satisfied or because the punishment was not worth it. There was no third option. There was certainly no room for a monkey who solved puzzles just because solving puzzles felt good.

Harlow called this third force intrinsic motivation. Then he designed a follow-up experiment. He gave some of the monkeys raisins when they solved the puzzle correctly. Suddenly, the monkeys started making more errors. Their performance deteriorated. They became less interested in the locks when the food was removed. The reward, designed to amplify behavior, had instead hollowed it out.