“I’ll be there at 2 p.m. sharp,” Kirsten assures me as we set up our next research meeting. I make note of it in my calendar—but I put it down as 3 p.m. It’s not that Kirsten is trying to fool me; she’s just deluded about her time-management skills. After a long history of meetings to which she shows up an hour late, I’ve realized I have to make allowances for her self-blinding optimism. I don’t have unique insight—any of her friends would make the same prediction. In the domain of punctuality, others know Kirsten better than she knows herself.

The difference between how you see yourself and how others see you is not just a matter of egocentrism. Like Kirsten, we all have blind spots. We change our self-conception when we see ourselves through others’ eyes. Part of the discrepancy arises because the outsider’s perspective affords information you yourself miss—like the fact that it looks like you’re scowling when you’re listening, or that you talk over other people.

There Is No Perfect Point of View

How do you cut through the fog and learn to see yourself—and others—clearly? Different perspectives provide different information on the self. To bring some order to all the things that can be known about you, it helps to divide them into four categories.

First, there are “bright spots”—things known by both you and others, like the fact that you’re politically conservative or talkative. Studies show that traits likeextroversion, talkativeness, and dominance are easily observable both to the self and to others. If everyone thinks you’re a chatterbox, you probably are.

Second are “dark spots”—things known by neither you nor others. These could include deepunconscious motives that drive your behaviors, like the fact that your relentless ambition is driven by the need to prove wrong your parents’ assumption that you’d never amount to much. T hird are “personal spots”—things known only by you, like your tendency to get anxious in crowds or your contempt for your coworkers. And finally, there are “blind spots”—things known only by others, which can include such factors as your level of hostility and defensiveness, your attractiveness, and your intelligence.

The most interesting are the latter two—personal spots and blind spots—since they involve discrepancies between how we see ourselves and how others see us.

Why You’re Less Transparent Than You Think

We’re not entirely deluded about ourselves. We have pretty unrestricted access, for instance, to what we like and believe; if you think you’re in favor of tighter regulation for car emissions or that Bon Iver is your favorite band right now, who am I to argue? Even if you don’t know the mysterious unconscious motives underlying what you like and do, you’re still the best source of information about your attitudes, beliefs, and preferences.

We often think others are aware of our anxiety or our darkest feelings, but research shows they’re actually poor judges of our emotions, intentions, and thoughts. Thomas Gilovich, a psychologist at Cornell, has found that numerous obstacles and psychological biases stand in the way of knowing how you’re seen by others. We overestimate the extent to which our internal states are detectable to others—a bias known as the “illusion of transparency.” We also overestimate the extent to which our behavior and appearance are noticed and evaluated by others—a bias known as the “spotlight effect.”

We’re good at judging our own self-esteem, optimism and pessimism, and anything to do with how we feel. So for instance, others may think you’re very calm when in fact you’re so anxious in large groups that your palms sweat and your heart rate soars.

Personal spots exist because others know how you behave, but they don’t know your intentions or feelings, explains Simine Vazire, director of thePersonality and Self-Knowledge Lab at Washington University. “If you’re quiet at a party, people don’t know if it’s because you’re arrogant and you think you’re better than everyone else or because you’re shy and don’t know how to talk to people,” she says. “But you know, because you know your thoughts and feelings. So things like anxiety, optimism and pessimism, your tendency to daydream, and your general level of happiness—what’s going on inside of you, rather than things you do—those are things other people have a hard time knowing.”