In one of psychology's most famous and stupefying experiments, Dan Simons made a video at Harvard that set out to test just how much our mind can see when it's busy.
"It started as a lark," Dan recalled. "There had been earlier experiments into visual cognition but in all of them, the display was so weird that it didn't feel like real life. So I thought: What if we make this whole thing live?"
(Before you read further, you might want to try the experiment for yourself .)
Together with Chris Chabris, Simons made a short film of Harvard students moving around and passing basketballs. One team wore white shirts, the other wore black. Simons himself is in the film but you won't recognize him, he says, because back then he had hair. When they finished making the film, Chabris and Simons asked volunteers to watch it and count the number of passes made by players wearing white. When the video ended, they asked viewers if they'd seen anything else. About half said no, they'd seen nothing.
What had they missed? A female student wearing a full-body gorilla suit walking into the scene, stopping in the middle of the frame, facing the camera, thumping her chest and walking off. She is on screen for approximately nine seconds.
The experiment has been shown repeatedly, around the world, in front of diverse audiences. I first saw it in Dublin, in an audience full of business executives. Like them, I was so focused on counting the passes I never saw the gorilla.
Simons was so stunned by the result that he says that for several years afterwards, he still kept expecting people to spot the gorilla. But results were always the same. In 1999, Simons and his colleagues published an account of the experiment entitled "Gorillas in our Midst" and, in 2004 they won an Ig Nobel prize for "achievements that first make people laugh and then make them think." Simons has since gone on to make an academic career studying how we pay attention.
His experiment, and now his book about the experiment have become justly renown. "The video gets talked about a lot in relation to national security forces and why they didn't see terrorists in their midst. My favorite one is a Baptist preacher was giving a sermon in which he referred to the gorilla and said that's why the Jews didn't spot Jesus for what he was!"
But of course, I love the experiment because it encapsulates one of the toughest problems in business: not seeing what, in retrospect, seems blindingly obvious. And why do we miss that? Because we are so busy paying attention to the stuff that everyone tells us is important. Pay too much attention to stock price or top line growth and you may, like Lehman Brothers or Bear Stearns, fail to notice you are going broke. Focus too much on your operating system, like Microsoft, and you miss the Internet. Worry too much about retail distribution -- like bookseller or resellers or music stores -- and you may not notice you've just been disintermediated.
Simons's new book has a profound lesson we all need to take to heart. The mind has a finite capacity. Focus on one thing and you will miss another. You may think your brain will expand infinitely to absorb however much it throws at you, but it won't. That leaves you with the single toughest question any leader faces: What deserves your attention today?