Are You
a Lark or
an Owl?
Each of us marches to the rhythm of
our chronotype, the internal circadian
clock that determines our productivity
peaks and valleys throughout each day
By Daniel H. Pink
A
fter working through the wee hours one
evening in 1879, Thomas Alva Edison sat in his
laboratory in Menlo Park, N.J., pondering a prob-
lem. He had figured out the basic principles of an
electric light bulb, but he still hadn’t found a substance that
worked as a low-cost, long- lasting filament. Alone in the lab,
he absentmindedly picked up a pinch of a sooty, carbon-based
substance known as lampblack that had been left out for an-
other experiment, and he began rolling it between his thumb
and forefinger—the 19th-century equivalent of squeezing a
stress ball or trying to one-hop paper clips into a bowl.
Then Edison had—sorry to do this, folks—a light-bulb mo-
ment. The thin thread of carbon that was emerging from his
mindless finger rolling might work as a filament. He tested it. It
burned bright and long, solving the problem. And now I’m writ-
ing this sentence, and perhaps you’re reading it, in a room that
might be dark but for the illumination of Edison’s invention.
Edison was a night owl who enabled other night owls. “He
was more likely to be found hard at it in his laboratory at mid-
night than at midday,” one early biographer wrote.
Indeed, human beings don’t all experience a day in precisely
the same way. Each of us has a “chronotype”—a personal pat-
tern of circadian rhythms that influences our physiology and
psychology. The Edisons among us are late chronotypes. They
wake long after sunrise, detest mornings and don’t begin peak-
THE SUCCESSFUL ATTITUDE
