I applied to one firm in every sector. This was the most half-hearted job search. “I’ll apply for that management consulting firm and this investment bank…” and I applied for five jobs altogether, because my heart wasn’t in it. And thankfully… I’m so glad I didn’t get any of those big jobs! Because that made this decision easier.

Day one of my first job out of college, my boss found out that I didn't know how to enter data into Lotus 1-2-3. That's a spreadsheet—ask your parents. His mouth dropped open and he said, ‘I can't believe you got this job without knowing that”—and then walked out of the room. I went home convinced that I was going to be fired. I thought I was terrible at everything… but it turns out I was only terrible at spreadsheets.

I was writing poetry. But I found the theater such an exciting experience that one day I went home to try. I had one character say to the other guy, “Hey, man, what’s happening.” And the other guy said, “Nothing.” I sat there for twenty minutes and neither of my guys would talk. So 1 said to myself, “Well, that’s all right. After all, I’m a poet. I don’t have to be a playwright. To hell with writing plays. Let other people write plays.” I didn’t try to write a play for a number of years after that first experience.

No one has a 5.0 in real life. In fact, when you finish school, the whole notion of a GPA just goes away. When you're in school, every little mistake is a permanent crack in your windshield. But in the real world, if you're not swerving around and hitting the guard rails every now and then, you're not going fast enough. Your biggest risk isn't failing, it's getting too comfortable.

So given a Time Turner, I would tell my 21-year-old self that personal happiness lies in knowing that life is not a check-list of acquisition or achievement. Your qualifications, your CV, are not your life, though you will meet many people of my age and older who confuse the two. Life is difficult, and complicated, and beyond anyone’s total control, and the humility to know that will enable you to survive its vicissitudes.

The friends with whom I sat on graduation day have been my friends for life. They are my children’s godparents, the people to whom I’ve been able to turn in times of trouble, people who have been kind enough not to sue me when I took their names for Death Eaters.