So I was in the grocery store the other day, picking up a few items on my way home from work. I overheard two women ahead of me in line discussing a mutual acquaintance who was apparently a little rough around the edges, but secretly a “very nice guy.”

“It just goes to show,” one of the women concluded, “You can’t judge a book by its cover.”

I did not interject myself into their conversation, but of course you can judge a book by its cover. That’s precisely what the covers of books are for. Judging the book.

That’s how you know what the book is called and who wrote it, and there’s often even plot synopsis on the back. Whether there’s a picture of a pirate clutching a buxom lass with their blouses blowing in the wind, or a knight confronting a fire-breathing dragon in the cover illustration, you’re going to get a fairly accurate impression of the genre.

The font of the title, the size of the print, the kind of binding, the review quotes, all of these things are deliberately chosen to give you information about the style of the content within. There’s a wealth of information right on the cover with which you can make a pretty good judgement of a book.

The same goes with people. Your hair cut, your clothes, your mannerisms, how you present yourself to others – these aren’t accidents, but deliberate choices you make. We constantly invent ourselves by the choices we make: how we choose to act and what we choose to do in any given situation.

So no one first impression can give the full picture of who a person is, just how they choose to be on that particular day. However, when you only meet someone once, then it is inevitable that you will form an opinion of them based on the information gleaned on that occasion – even if it’s only the cover of the book. It’s all you have to go on.

Which is why how you dress, act, and present yourself in job interviews is critical, and it’s fair game for employers to make their decisions about you based on the choices you make. How professional you are, how serious you are about the job, how savvy you are about the style of the company or industry culture – all of these can be indicated simply by your clothing and grooming choices.

While everyone should be treated equally regardless of fashion, in many situations how you are dressed matters. At a professional conference, a woman in business casual attire seems more important than a woman in yoga pants. In a business setting, a man in a suit is accorded more respect than a guy in jeans and a polo shirt.

And recent psychology research has found that dressing more formally actually makes people think differently. When people dress up they feel more powerful, and this allows them to make better decisions.

So should you start wearing a suit to work every day? Adam Galinsky from Columbia Business School says not necessarily: “If you associate those clothes with power and confidence, it’s going to have a huge impact on your performance,” he says. But not everyone has that same association for power suits, so it really comes down to what Galinsky calls “the symbolic meaning of the clothes is to the person.”

Dressing in what you perceive to be the clothing of the most well-regarded and competent person for a role will have a psychological effect on you, allowing you to actually perform as a more competent person in that role.

So while in many workplaces it’s perfectly acceptable to wear jeans, not all jeans are created equal. A worn-out, torn, stained, ill-fitting or outdated pair won’t help how you’re perceived or apparently how you’ll perform.

So the next time you’re heading out to work without shaving or in the wrinkled shirt you pulled out of a pile on the floor, remember that you may be perceived as less professional or competent because of your appearance. And that perception may even have some truth to it. Your clothes don’t define who you are as a person, but they do have a powerful influence over how you feel and act.

And you can’t fault employers for judging you by your appearance in job interviews. You choose how to present yourself, and it’s really all they have to go one that day. It might be judging a book by its cover, but that’s what the covers of books are for.

(Which makes me wonder what are we going to judge things on once e-books completely take over…)

See also:

Study: What you can tell about someone by their facial hair
It’s true: You really can accurately judge a person by their shoes
Too hot for the office? What not to wear to work (even in summer)

Peter Harris

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