Mark Zuckerberg wears the same grey T-shirt every day.
Being a boring dresser helps him take care of his brain, the Facebook CEO says.
“I really want to clear my life to make it so that I have to make as few decisions as possible,” he explained in a recent Q&A.
A growing body of research shows that the willpower used in decision-making is like a muscle.
As Florida State psychologist Roy Baumeister details in his book “Willpower: The Greatest Human Strength,” you can only use so much willpower in a given day.
That’s why many executives, like Zuck, avoid tapping into their willpower reserves by limiting the number of decisions they have to make. “I feel like I’m not doing my job if I spend any of my energy on things that are silly or frivolous about my life,” he said.
As Baumeister’s research has revealed, willpower and decision-making are interconnected. The house you grew up in, the number of decisions you made today, and what your friends are doing all affect your decisions in weird ways.
Zuckerberg isn't alone; Barack Obama is a boring dresser, too.
He's always clad in a blue or grey suit.
'I'm trying to pare down decisions,' he told Vanity Fair. 'I don't want to make decisions about what I'm eating or wearing. Because I have too many other decisions to make.'
Obama isn't the only one concerned for his decisions: A 2011 study of 1 million people around the world found that people think that self-control is their biggest weakness or character failure.
Baumeister and other decision researchers talk about 'ego depletion,' which states that you only have so much mental energy to make decisions or exercise self-control in a given day.
The term is a nod to Sigmund Freud, the Austrian doctor who invented psychoanalysis.
'Freud speculated that the self, or ego, depended on mental activities involving the transfer of energy,' the New York Times reports. '(His) experiments demonstrated that there is a finite store of mental energy for exerting self-control.'
That means the more complex the problem, the earlier in the day it should be tackled.
'Even the wisest people won't make good choices when they're not rested and their glucose is low,' Baumeister told the New York Times. 'That's why the truly wise don't restructure the company at 4 p.m. They don't make major commitments during the cocktail hour. And if a decision must be made late in the day, they know not to do it on an empty stomach.'
Grocery retailers discovered this decades ago.
Candy and soda are positioned at the checkout line to take advantage of decision fatigue: You just waded through the whole store making dozens of decisions, so the quick hit of energy in a Dr. Pepper or a Snickers looks even more attractive than usual.
Obama's decision to 'sleep on it' -- it being whether or not to raid Osama Bin Laden's compound -- aligns with psychologists' recommendations for complex decision making.
'Because your conscious attention is limited, you should enlist the help of your unconscious,' according to the Harvard Business Review.
Even if you don't have the option to delay your decision for long, engaging in another activity will take your mind off your dilemma, and allow your unconscious to surface.
Breakthroughs in network science -- the study of social groups -- have revealed how many things we tend to think of as being individual, like whether you get fat or stop smoking, are actually collective.
As James Fowler of the University of California, San Diego, and Nick Christakis of Harvard Medical School have found, our behaviours are contagious.
If your best friend gets fat, you have a 57% greater chance of getting fat, too. If a close colleague quits smoking, you have a 34% greater change of quitting smoking, too.
Network science has insights into productivity, too.
When researchers tracked the successes of individuals at an aerospace company, including patents and products those individuals brought to market, they found that who a given engineer knew was tremendously important.
After experience, the relationships that an individual had were the greatest predictor of success. The people who had relationships up and down the hierarchy and across departments were the most likely to succeed by the company's metrics.
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