Many people see the decline of embarrassment as a good thing. "Why shouldn't I be able to do X?" People often say this after having done something outrageous or transgressive. But this misunderstands the distinction between embarrassment - a mild but necessary correction of inappropriate behavior - and shame, which is a stronger emotional response usually involving feelings of guilt about more serious breaches of conduct.

Not long ago, I watched half a dozen people get their teeth whitened in the middle of a shopping mall. I was riveted by the spectacle of these men and women in repose on their clinical white lounge chairs. Their faces were in a sort of dental rictus, with oversized trays of peroxide solution crammed in their mouths and little blue paper bibs draped around their necks to catch their drool. Official-looking "technicians" (that is, untrained minimum-wage workers who simply handed the customers their bleaching trays) bustled around in white coats, readjusting the LED lights that were pointed at patrons' teeth. It was like happening upon a car wreck; I couldn't look away. I wondered who would be confident or crazy enough to get a cosmetic dental procedure performed in public. It turns out that kiosk-style teeth whitening franchises are a nationwide business. With names like "iBrite Express," "Bright Smiles Express," and "WOW Smile XPress," these peddlers of perfect smiles promise whiter teeth in a mere fifteen minutes - with results that they claim will last for years.

It is not only public grooming that you'll see more of these days; public displays of affection have become more frequent (and more amorous) as well. As one young Manhattan resident recently complained in the New York Times, "Everywhere I go, people are fondling each other as if the entire city were a cheap motel room." At work, over-sharing is becoming as vexing an office problem as gossip. Wall Street Journal reporter Elizabeth Bernstein wrote recently of the challenge of erasing from her mind the image of a colleague who, in pursuit of his bicycling hobby, described "shaving his entire body to reduce aerodynamic drag." We have even devised an acronym - TMI, or "Too Much Information" - to capture the uncomfortable experience of listening to people natter on about their personal problems.

What ever happened to embarrassment? Why are an increasing number of us comfortable bringing our private activities - from personal hygiene to intimate conversation - into public view? Bernstein and others place some of the blame on the desensitization wrought by reality television and social networking sites like Facebook, both of which traffic in personal revelation. To be sure, television and Internet video sites such as YouTube have made all of us more comfortable in the role of everyday voyeurs. We watch others cook, work, shop, argue, sing, dance, stumble, and fall - all from a safe remove. The motley denizens of reality television regularly put themselves into questionable and embarrassing situations so that they can later discuss, for our viewing enjoyment, how questionable and embarrassing their conduct was. If we are less easily embarrassed, it must be in part from vicariously experiencing so much manufactured embarrassment on the screen.

Many people see the decline of embarrassment as a good thing. "Why shouldn't I be able to do X?" people often say after having done something outrageous or transgressive. But this misunderstands the distinction between embarrassment - a mild but necessary correction of inappropriate behavior - and shame, which is a stronger emotional response usually involving feelings of guilt about more serious breaches of conduct.

Today, what used to cause embarrassment now elicits little more than a collective shrug. In our eagerness to broadcast our authentic experiences and have our individuality endorsed, we reject embarrassment as if it were some fusty trapping of a bygone age. But we haven't eliminated embarrassment; we have only upped the ante. "Your slip is showing" used to be the most embarrassing sartorial faux pas a lady could commit. Now we regularly witness "nip slip" from female celebrities whose shirts mysteriously migrate south during public appearances - or during Super Bowl halftime shows. As the boundary between public and private has dissolved, so too has our ability to distinguish between embarrassing and appropriate public behavior. The result is a society often bewildered by attempts to impose any standards at all.

Unlike many other emotions, embarrassment must be learned. Infants know nothing of this emotion, and parents often use the threat of embarrassment to teach young children correct and incorrect behavior: "If you say that in public, you'll embarrass yourself," we say to the toddler with a penchant for scatological chitchat. Embarrassment is also a social emotion; its occurrence requires the real or imagined presence of others. Belch at a dinner party and you will likely feel embarrassed; do it while home alone and you're unlikely to feel abashed. Because it is a learned behavior grounded in social relations, embarrassment is a kind of barometer for a society's notions of civility.

In fact, as the science of embarrassment suggests, it is part of what makes civility possible. In Behavior in Public Spaces, published in 1963, sociologist Erving Goffman described our public actions, from greeting friends on the street to answering questions posed by strangers, as signals of the strength of our commitment to our social communities. "What the individual thinks of as the niceties of social conduct," Goffman argued, "are in fact rules for guiding him in his attachment to and detachment from social gatherings." These are what mark us as belonging, or not. "More than to any family or club, more than to any class or sex, more than to any nation, the individual belongs to gatherings, and he had best show that he is a member in good standing," Goffman wrote.

When we ignore these social niceties we risk not only embarrassing ourselves, but also sowing doubt in others about our social standing. No one enjoys being embarrassed. But it brings us all together as a community by reinforcing norms and policing the boundaries of propriety. Writing recently in Greater Good magazine, University of California-Berkeley psychologist Dacher Keltner argued that the subtle signals of embarrassment - averting one's eyes or pressing one's lips together -are "a sign of respect for others, our appreciation of their view of things, and our commitment to the moral and social order." Far from dividing people, embarrassment "can be a peacemaking force that brings people together - both during conflict and after breeches of the social contract, when there's otherwise great potential for violence and disorder." By expressing embarrassment we put others at ease by reinforcing our commitment to group norms. Keltner encourages us to see embarrassment as "a window into the ethical brain."

But in our nonjudgmental, individualistic culture, it is often uncomfortable and occasionally dangerous to attempt to enforce social norms. Even when people are objectively behaving badly - like the people who flout cell phone bans in trains or doctors' offices and impose their conversations on everyone else around them - it is often difficult to muster the courage to tell them to be quiet. In his book Embarrassment, psychologist Rowland S. Miller argues that, far from being inappropriate, embarrassment "is often a desirable, correct response to social predicaments." Our fleeting sense of embarrassment when reminding someone else to follow the rules is normal, and as Miller reminds us, people who are unwilling to express embarrassment mark themselves as socially suspect. "A capacity for embarrassment is a marker of normal humanity," writes Miller. Or at least it should be.

At the very least, embarrassment serves as a reminder that no matter our circumstances, we are more alike than not. Pier Forni, who founded The Civility Initiative at Johns Hopkins University thirteen years ago, recently told Obit magazine, "We are more and more concerned with our own pursuit of personal goals. As we engage in a mad rush for the attainment of our personal goals, we don't seem to have the time or see the point of slowing down for the purpose of being kind to others." Nor have we yet found the right balance between connecting with others and TMI. So the next time you feel like sharing the details of your upcoming bunion surgery with your coworkers, resist. You will not only avoid potential personal embarrassment, but you might just make one small step toward improving civility for us all.