I can't believe I'm admitting this, but I've lost count of the number of times I’ve watched the YouTube video of Susan Boyle's performance on Britain's Got Talent. At least I'm not alone. To date, more than 40 million people have hit the site to see an unemployed, never-married, frizzy-haired 47-year-old raise the roof belting “I Dreamed a Dream” from Les Misérables.

Like everyone else, I was initially arrested by the comic incongruity of the spectacle: ugly singer, beautiful song. But now I'm fascinated by my—our—fascination. Why was it such a shock that Boyle is so good? Why did a huge crowd laugh out loud at the very notion that she had real talent? Why would most of us, let's face it, have done the same? In short, if a person's gifts are hidden, why do we so often assume that those gifts don't exist?

Susan Boyle's great talent is almost as old as she is, and yet she needed uncommon nerve and freakish luck for anyone to see it. That's the measure of our collective blindness to omnipresent human worth. From the making of social policy to the minutiae of social interaction, our society assumes the worst about whole swaths of people, when experience suggests we should assume the best.

Every time I encounter the perception of low-ranking U.S. soldiers as yahoos or trigger-happy atrocity-committers-in-waiting, I remember the reality I witnessed so many times at the front gate of U.S. military bases in Iraq. Some very young, very badly paid, and very uncomfortably armored man would be standing in the desert sun, managing a highly complex task all too little known to his loftily credentialed civilian counterparts: dealing directly—and skillfully and respectfully—with the Iraqi public.

This required negotiating one mental maze after another: A man says he is being threatened by a militia that is planning to ambush U.S. troops this afternoon. Is this a useful piece of information? A misguided complaint? A trap?

Similarly, when I hear welfare mothers portrayed as shiftless cheats, I think of my husband's mother, whom his father abandoned with nine children and not a dime of support. That welfare mother was not a sponge, she was a saint—and she can't have been the only one. Every time I see domestic help treated as worthless drudges, I remember my own grandmother. In a different life, she might have run the world; in her actual life, she came to the U.S. at age 13 to clean houses. Over time, Nana's outward social position improved—but her intrinsic human quality was sterling from Day One.

These are just a few examples from my own, very fortunate life. If we concede—and why wouldn't we?—that it is a heroic feat to survive on less than $1 a day, there are more than 1 billion heroes walking the earth today.

It's not all a question of class. Stay-at-home mothers of every stripe are routinely treated as morons. Overweight people are openly ridiculed (and don't tell me they are ridiculed out of great concern for their health—thin, pretty drug addicts are glorified). Old people may as well chuck their mental marbles out the window, for all the credit they get for keeping them. Meanwhile, their amazing caregivers have the social status of paper towels. Which reminds me: Long before her star turn, Susan Boyle did something truly laudable. She took care of her mother.

Don't get me wrong. Normally, I am the last person to downplay the importance of cosmetics. When it comes to the ongoing international debate about whether Boyle should make herself over—or rather, now that she's gotten a decent haircut and a Burberry scarf, whether she should make herself over some more—I find it every bit as dehumanizing to hope she remains forever frumpy as to demand that she pour herself into the standard mold of celebrity.

Appearances will always count, and there’s no reason they shouldn’t. But they should not count so much that they allow us to miss almost everything valuable about almost everyone almost all the time. Ultimately, it's not Susan Boyle who could really use a makeover. It's the rest of us.