framing it as a polarity misses its real shape. there is a cycle, 5 things follow on from each other. enthusiasm leads to joy, joy leads to caution (settling after release), caution leads to regret, regret leads to correction and correction leads to enthusiasm. conversely, as those 5 in that path is productive, if one of them builds up and dwells, you are stuck in anger, you need to calm, if you are overly calm, you are bored, which is broken by joy, if your joy overflows into delerium, caution tempers it to calm. if your caution has rotted into fear, you need to have a surprise to release that to bring you back to enthusiasm, and if that leads to anger, you need to ... well, something like this. training on recognising the state you are in, so when you notice you are depressed, what you need to apply is a sharp cut on the wood which is swallowing your joy, just as a tree penetrates the earth and stops it from moving.