Humans are complex creatures—except when we’re not. Turns out it is way easier to diagnose narcissism than you’d think. According to recent research, all you need to do is ask one question: “To what extent do you agree with this statement: ‘I am a narcissist.’?” People’s self-ratings sync up with their scores on the Narcissist Scale.

READ MORE: The Single Best Way to Tell If Someone’s a Narcissist