Shane Parrish, writing in Farnam Street newsletter:
Few things are more important in life than avoiding the wrong people. It’s tempting to think that we’re strong enough to avoid adopting the worst of others. But that’s not how it typically works. The changes are too gradual to notice until they are too large to address.
Over a long enough timeline, bad people eventually destroy themselves. They ignore relevant data because it doesn’t agree with them, they take unwarranted risks, they end up alone, without any friends. They might achieve external success, but they lack inner calmness and clarity.
Just as you watch what you put into your body or your mind, closely look at who you spend your time with. Are they kind? Are they honest? Are they thoughtful? Are they helping you or pulling you down? Are they reliable? Are they clear thinking? In short, are they the things you want to become? If not, don’t tempt fate, cut bate.
Distance yourself from the people you don’t want to become. Cultivate people in your life that make you better. People whose default behavior is your desired behavior. If circumstances make this difficult, choose among the eminent dead.