In the mid-1990s, I went to grad school at night to get my master's degree in literature, assuming it would be like book club without the wine. My first class, the portal course that would prepare me for all seminars to come, was led by a celebrated professor who, in his spare time, hosted a daily show on NPR. My first paper in that first class was about whether or not a reader should consider the author's biography when interpreting a novel. And on this crucial paper, I got my first C since high school econ. Actually, I believe it was a C minus.

Suddenly it seemed I had no aptitude for the very thing I most wanted to do—write. But I had paid for the semester; I had committed to two years of eating Trader Joe's frozen burritos and shopping exclusively at a brand-new store called Old Navy. So I met with the professor to review the many missteps in my argument, started reading more than what was assigned, and pored over my notes each night after class, jotting down questions, filling in holes.

One night near the end of the semester, I had to give a presentation on Toni Morrison's Sula. The Q&A period lasted until the final minute of class, and I left knowing I had defied expectations. I understood something essential about the book. I had a way to talk about it that was meaningful, even compelling. I had thoughtful responses to my classmates' questions.

On the ride home from class that night—after my professor called my presentation "insightful"—it occurred to me that my aptitude was never the problem. It was my work ethic. If I was willing to read slowly, think hard, and rewrite endlessly, I'd always have something worthwhile to contribute.

And this is how I know that self-esteem is less about adding a shiny new bell to your bike or learning how to pop a wheelie than it is about recognizing that you don't always know what to do but, lookee there, you figure it out.

Kelly Corrigan's memoir, The Middle Place (Voice), is in bookstores now.