Don’t make enemies you don’t need. The kid you snub at sixteen could be your coworker at twenty-six.

A grudge made at sixteen is cheap at the time and oddly durable afterwards. Towns and industries are smaller than they feel from inside a school, and the people around you keep turning up: on a shift rota, at a job interview, on the other side of a hiring decision. Being decent is not naive, it is just long-range thinking.

You do not have to be friends with everyone. Just avoid making the free enemies: the snub that was for an audience, the joke at somebody’s expense. Leave people with no particular reason to be glad when things go badly for you.