Here’s a holiday I can really get behind: World Introvert Day, which has been celebrated every January 2 since 2011. My wife and I are both outspoken introverts, if there can be such a thing, and we’re delighted that someone has thought to call attention to this personality trait present in roughly half the human population! (It’s especially prominent among writers, artists, musicians, philosophers, scientists, and of course superheroes.) Introverts may not call much attention to themselves, but that doesn’t mean they’re all shy or withdrawn. They just need to recharge in different ways than extroverts. So give an introvert a hug today. Or, maybe a fist bump. Better yet, a discreet wave from across the street. Or just send a text. Postcards are even better!