The Intelligence Trap: Revolutionise your Thinking and Make Wiser Decisions

by David Robson

The Post Office had just invested heavily in machines that could sort letters according to postcodes, but to use these machines, their 10,000 postal workers had to learn how to type and use a keyboard, and Baddeley’s job was to discover the most efficient schedule for training. The assumption of many psychologists at the time had been that intensive training would be better – the postmen should be allowed to devote a few hours a day to mastering the skill. And this was indeed the way that the workers themselves preferred: they were able to see real progress during that time; at the end of their sessions, their typing felt much more fluent than at the beginning, and they assumed this carried over into long-term memory. For comparison, however, Baddeley also created a few groups that learnt in shorter stretches, over a longer period of time: just one hour a day, compared to four. The workers in this group didn’t seem to like the approach; they lacked the sense of mastery at the end of their session and didn’t feel like they were progressing as quickly as those taking the longer sessions. But they were wrong. Although the sessions themselves felt unsatisfying compared to those of the people who developed more proficiency in a single day, these subjects ended up learning and remembering much more in relation to the amount of time they were putting into it. On average, a person with the ‘spaced’ approach mastered the basics within thirty-five hours, compared to fifty hours for ...