Can you use humor in a college essay?

RReaders in Stanford's admissions office want to finish an essay feeling they have met a person, and serious essays often fail that test without the writer noticing. An applicant writing about existentialism told the story of Bob Dylan walking off The Ed Sullivan Show after the network objected to his song. She wrote that the show had 86'd the piece, and added in parentheses that she had learned the term punching an 86 next to the pickles on a restaurant order. The paragraph was about Sartre.

That small addition told the reader she had a job, and it balanced heavy philosophy with pickles, so the reader liked her more for it. A few devices do this kind of work, and each fails in its own way.