A good friend and colleague, a real extrovert, sent me a link to a shirt recently that she knew I’d appreciate. “Sorry I’m late,” the T-shirt reads. “I didn’t want to be here.”

I laughed — of course I laughed. I’m as introverted as she is outgoing, and we frequently play out our roles in tandem. At parties, she takes the lead; at meetings, she does the talking. I get to nod and smile.

But the shirt also made me wince, because it perfectly encapsulated the suspicion I’ve started to develop that my introversion is an excuse for something else. I’m shy, yes. But am I also rude? In a contest between my manners and my preferences, am I allowing my preferences to win?