Marvin is a delusional dater. He somehow talked the gorgeous Maria into going on a date with him, and today is the day. Maria is way out of Marvin’s league but he lacks self-knowledge. He thinks he is better looking, better dressed, and more interesting than he really is. Yet his illusions about himself serve a purpose. They give him self-belief and as a result the date goes better than it would have done otherwise. Maria is still out of Marvin’s league, but is at least impressed by his nerve and self-confidence, if not by his conversation.

The case of the delusional dater suggests that self-knowledge doesn’t necessarily make you happier or more successful, at least in the short term. According to social psychologists Timothy Wilson and Elizabeth Dunn, there are physical and mental benefits associated with maintaining slight or moderate self-illusions, such as believing one is more generous, intelligent, and attractive than is actually the case. There are some truths about ourselves which, like Marvin, we are better off not knowing.

Real world examples of the benefits of moderate self-illusions are not hard to find. In my experience as a university teacher, average students who believe they are better than that tend to work harder and do better than average students who know their own limitations. Studies of HIV-positive men have shown that they are more likely to practice safe sex if they believe they are unlikely to get AIDS. Sometimes positive self-illusions can be even self-fulfilling. Studies of women at weight loss clinics have shown they are more likely to lose weight if they believe they are going to lose weight.

My favourite example of the power of self-illusions is a famous study of snake-phobic subjects who were played what they believed were the sounds of their own heartbeats as they were shown slides of snakes. In fact, instead of their own racing hearts, they were played the steady heartbeats of someone with no fear of snakes. As a result, the snake-phobic subjects inferred that they weren’t that scared of snakes after all and became less snake-phobic.

Knowledge of how generous, attractive, or frightened you are might not sound like “self-knowledge.” We like to think of self-knowledge as something deeper, as knowledge of the “real you.” But the real you isn’t something apart from your thoughts, motives, emotions, character traits, values and personality. Knowledge of these things is knowledge of the “real you,” and the question remains why knowledge of the real you should matter. Most of us have heard of the ancient command to “Know thyself” but few have dared to ask what good it does.

Low-end explanations of the value of self-knowledge say that self-knowledge is a good thing because it makes you happier or more successful. High-end explanations say that the real point of self-knowledge is that having it enables us to live more authentic and meaningful lives. From this standpoint it doesn’t matter if self-knowledge doesn’t guarantee happiness or success. That was never the point of “Know thyself.”

High-end explanations of the value of self-knowledge are seductive but don’t really work. To be authentic is to be true to yourself, and you might wonder how you can be true to yourself, to who you really are, if you don’t know yourself. Actually, it’s easy to show that authenticity is possible without self-knowledge. Suppose the opportunity arises to cheat in a card game but you don’t cheat because you aren’t a cheat. In refraining from cheating you are being true to yourself but what makes you refrain from cheating is the fact that you aren’t a cheat. You don’t need to know you aren’t a cheat for you not to cheat. You can be true to yourself regardless of whether you know yourself.

Socrates said the unexamined life is not worth living. Could this be why self-knowledge matters? The idea that self-knowledge has something to do with finding meaning in your life is promising but controversial. There is plenty of evidence that people find their life choices more meaningful when they are consistent with the kind of person they think they are, but the kind of person you think you are may be quite different from the kind of person you actually are. Being mistaken about the kind of person you are needn’t prevent you from finding your life meaningful on its own terms.

Am I saying that self-knowledge is worthless? Not at all. What I’m saying – and this might be a surprising thing for a philosopher to be saying – is that self-knowledge is overrated in our culture. The truth of the matter is not that you can’t live authentically, meaningfully, or happily without self-knowledge, but that a modicum of self-knowledge might, depending on the circumstances, improve your prospects of living in these ways. While self-knowledge is no guarantee of happiness, you are unlikely to do well in life if you are grossly self-ignorant. Marvin’s self-illusions might get him through his date with Maria but in the longer term he will save himself the pain of repeated rejection if he stops kidding himself.

“While self-knowledge is no guarantee of happiness, you are unlikely to do well in life if you are grossly self-ignorant.”

The same applies to talentless contestants of reality TV talent shows. It’s hard not to think that delusional contestants who believe they can sing like Michael Jackson would in the end live happier lives if they learned to handle the truth about themselves. How can you plan your life if you are completely clueless about what you are good at? At some point, you need to come to terms with the real you, and the challenge is to figure out how to do that.

Writing in the 17th century, René Descartes saw self-knowledge as strictly first-personal, as the product of a special kind of mental self-examination. Descartes was wrong. We aren’t unbiased observers of our own inner selves, and the studies suggest that the stories we tell ourselves about ourselves aren’t to be trusted. We all like to think well of ourselves.

A better bet is to try to see yourself through the eyes of others. When it comes to the real you, your friends, colleagues, and nearest and dearest probably have deeper insights than you do. The self-knowledge you get by social interaction is indirect and third-personal but that’s okay. For example, you might not think that you are generous but if everyone you are close to thinks that you are tight with money then that trumps your self-conception. In this case, other people know the real you better than you know the real you.

Of course, seeing ourselves through the eyes of others can be hard to do, especially when their opinion is unflattering. That’s one of many factors which make worthwhile self-knowledge so hard to get. So if self-knowledge is something which matters to you then here is some practical advice: try to accept that reliable self-knowledge is not something you can get by self-examination. Instead, try to see yourself as others see you, and give up any idea that you are always the best judge of the real you. Even with the help of others, a degree of self-ignorance is unavoidable. But if self-ignorance is part of the human condition, so is the ability to get by without really knowing ourselves.

This article originally appeared in LUX Magazine.