“It’s not about luck,” my friend Andrew insists, “it’s about gratitude.”

Andrew is not some sort of New Age guide, in case you were wondering. He is a slightly curmudgeonly tax preparer and not given to feel-good platitudes.

He was refuting what I had said, which was that luck has played a significant role in my life. When good things happen to me, I don’t believe it’s only because I worked hard.

“Lots of people work hard,” I told Andrew. “Not everyone had the head start I did.”

By “head start,” I am usually referring to my mom and dad, who were the equivale...