The principle for Day #39 on the 101-day book report says: "Find your calling and then use your talents to make it so."
You get your genes and your toolbox from your parents and your upbringing, but I think your calling stems from a completely different source. And if philosophy was my calling, I might even have read a book that explains what that source might be.
But growing up, I always considered myself a writer, even before I had any skills. And when my High School English teacher told me that I'd never be a writer because my penmanship was bad, I realized that a lot of assholes miss their calling, too.
And there's the rub; you don't get to pick what your calling is--you only get to decide whether to face it.