I am an essayist, for better or worse. I don't suppose many young people dream of becoming essayists. Even as nerdy and bookish a child as I was fantasized about entering the lists of fiction and poetry, those more glamorous, noble genres on which Nobels, Pulitzers and National Book Awards are annually bestowed. So if Freud was right in saying that we can be truly happy only when our childhood ambitions are fulfilled, then I must be content to be merely content.
 I like the freedom that comes with lowered expectations. In the area of literary nonfiction, memoirs attract much more attention than essay collections, which are published in a modest, quasi-invisible manner, in keeping with anticipated lower sales. But despite periodic warnings of the essay's demise, the stuff does continue to be published; if anything, the essay has experienced a slight resurgence of late. I wonder if that may be because it is attuned to the current mood, speaks to the present moment. At bottom, we are deeply unsure and divided, and the essay feasts on doubt.
 Ever since Michel de Montaigne, the founder of the modern essay, gave as a motto his befuddled "What do I know?" and put forth a vision of humanity as mentally wavering and inconstant, the essay has become a meadow inviting contradiction, paradox, irresolution and self-doubt. The essay's job is to track consciousness; if you are fully aware of your mind you will find your thoughts doubling back, registering little peeps of ambivalence or disbelief.
 According to Theodor Adorno, the iron law of the essay is heresy. What is heresy if not the expression of contrarian doubt about communal pieties or orthodox positions? This is sometimes called "critical thinking," an ostensible goal of education in a democracy. But since such thinking often rocks the boat, we may find it less than supported in school settings. Typically, the exercise of doubt is something an individual has to cultivate on his or her own, in private, before summoning the courage to air it, say, in an essay.
 Recently, with fiercely increased competition for admission to the better colleges, the "common app" essay has become an obsessive focus on the part of high school administrators, parents and students. This part of the college application requires each applicant to file a personal statement, a prose reflection conveying individual sensibility, experience or worldview.
 Tutors advertise on lampposts for after-school courses to prep the college aspirant for the most seductive, winning common app. (I am delighted to see this career path opening for indigent essayists.) The problem is that, more often than not, the applicant is expected to put forward a confident presentation of self that is more like an advertisement, a smooth civic-minded con job, circumventing the essay's gift for candid, robust self-doubt.
 When my daughter Lily, now a college freshman, was applying to schools, she wrote what I thought was a perfect common app essay about her mixed attraction to the idea of melancholy. Her high school counselor, while conceding it was well written, forced her to abandon it because it might give schools the wrong impression that she was a "downer." Earlier, Lily, whom I had encouraged to wear her ambivalence proudly, was reproved by teachers for writing papers that failed to support one side of a debate, instead arguing the validity of both positions.
 I got it that they wanted her to sharpen her rhetorical ability. Argumentation is a good skill to have, but the real argument should be with oneself. Especially when it comes to the development of young writers, it is crucial to nudge them past that self-righteous inveighing, that shrill, defensive one-track that is deadly for personal essays or memoirs, and encourage a more polyphonic, playful approach. That may be why a classic essay technique is to stage an inner debate by thinking against oneself.
 Doubt is my boon companion, the faithful St. Bernard ever at my side. Whether writing essays or just going about daily life, I am constantly second-guessing myself. My mind is filled with "yes, buts," "so whats?" and other skeptical rejoinders. I am forever monitoring myself for traces of folly, insensitivity, arrogance, false humility, cruelty, stupidity, immaturity and, guess what, I keep finding examples. Age has not made me wiser, except maybe in retrospect. My wife sometimes complains that I will never admit I am wrong. Of course I do - granted, less than I should, but it's not just because I am stubborn and hate to concede a point in the heat of argument. The main reason is that a part of me always assumes I'm wrong and at fault, to some extent; this is so obvious to me that it needn't bear stating. In any case, I often forget to say it aloud. But I certainly think it.
 Strangely enough, doubt need not impede action. If you really become friends with your doubt, you can go ahead and take risks, knowing you will be questioning yourself at every turn, no matter what. It is part of living, a healthy evolutionary adaptation, I would imagine. The mistake is in trying to tune out your doubts. Accept them as a necessary (or at least unavoidable) soundtrack.
 The only danger, then, is becoming smug about one's capacity for doubt—the essayist's occupational hazard, to which I periodically succumb. I have found the exercise of doubt to be an enormous help in writing essays, because it lets me start out with the knowledge that I may very well not achieve perfection on the page. Then I can forgive myself in advance for falling short of the mark, and get on with it.
Phillip Lopate, who directs the graduate nonfiction program at Columbia University, is the author, most recently, of "Portrait Inside My Head" and "To Show and to Tell."