The word “computer” was, for centuries, a job title. From the 1600s onward, human computers did calculations—initially by pen and paper—to create navigational tables, accounting ledgers and the like. By the 1960s, the workers had slide rules and mechanical calculators to help them, but these jobs were still around. NASA relied heavily on flesh-and-blood computers, like Katherine Johnson and her team of African-American women, to do calculations for the early space missions, as recounted in the 2016 feature film Hidden Figures.
Today, a smart watch can add and subtract numbers billions of times faster than any human being. So you might assume that NASA has no need for human computers in the 21st century.
But you’d be wrong. The programmers, mathematicians and computational physicists working for NASA now far outnumber the human computers employed at the agency in the 1960s. Despite a billion-fold increase in the capability of the machines, human jobs weren’t lost—they multiplied. The reason that happened tells us a lot about intelligence, both human and artificial.
It turns out that human intelligence is not just one trick or technique—it is many. Digital computers excel at one particular kind of math: arithmetic. Adding up a long column of numbers is quite hard for a human, but trivial for a computer. So when spreadsheet programs like Excel came along and allowed any middle-school child to tot up long sums instantly, the most boring and repetitive mathematical jobs vanished.