Both potter is jealous of potter and craftsman of craftsman; and poor man has a grudge against poor man, and poet against poet.

Rivalry runs hottest between people who are closest in position. You do not envy the person whose life bears no resemblance to yours; you envy the one doing the same work, in the same conditions, one step ahead. The comparison is available and the gap is small enough to feel unfair. People who ought to be allies are often the least able to be, and it costs them both.

Look at whom you quietly measure yourself against and notice how similar their situation is to yours. Then do the unlikely thing and help one of them. Rivalry at that range is usually more expensive than whatever it was protecting.