This is What Most People Get Wrong About Willpower
Ego-depletion is a theory that willpower is connected to a limited reserve of mental energy, and once you run out of that energy, you’re more likely to lose self-control. This theory would seem to explain your post-work defeat. But new studies suggest that we’ve been thinking about willpower all wrong and that the theory of ego-depletion isn’t true. Even worse, holding on to the idea that willpower is a limited resource can actually be bad for you, making you more likely to lose control and act against your better judgment.
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