Why Are Some People Selfish?

The Brain





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Selfish people's brain's spike in activity when someone is nice to them. PathDoc/Shutterstock

Most of us are at least a little selfish, but some more so than others. In order to get what we want in life we tend to reward those who are good to us by being good back to them, and punish those who aren't. But there are a minority of people, known as “Machiavellians,” who pay no regard to these social norms.