One day, when my brother was 18, he waltzed into the living room and proudly announced to my mother and me that one day he was going to be a senator. My mom probably gave him the “That’s nice, dear,” treatment while I’m sure I was distracted by a bowl of Cheerios or something.

But for fifteen years, this purpose informed all of my brother’s life decisions: what he studied in school, where he chose to live, who he connected with, and even what he did with many of his vacations and weekends.

After almost half a lifetime of work later, he’s the chairman of a major political party and a judge. He also ran for state congress in his 30s and barely lost.

Don’t get me wrong. My brother is a freak. This basically never happens.

Most of us have no clue what we want to do with our lives. Even after we finish school. Even after we get a job. Even after we’re making money. Between ages 18 and 25, I changed career aspirations more often than I changed my underwear. And even after I had a business, it took another four years to clearly define what …