A group of people were travelling in a boat. One of them took a drill and began to drill a hole beneath himself.
His companions said to him: "Why are you doing this?" Replied the man: "What concern is it of yours? Am I not drilling under my own place?"
Said they to him: "But you will flood the boat for us all!" (Quoted in Midrash Rabbah, Vayikra 4:6).
I've been haunted by this story as I think of people who refuse to wear a mask during the pandemic of an airborne virus. They think it's their own business but they can't see how their choice affects us all.
Exactly