I'm re-reading (sorta half-browsed it before, like 20 years ago) this superpopular book about Phleg, Sang, Chol, Mel temperaments. I needed the education, for real. (I was going to write more but maybe it's boring for the reader when I do all these ... I'm just assuming ... ok, maybe I'll put it in the comments.)
I think I get what the four are now. In this picture I just sketched,
What is 'suga'? I don't know, it's like 'highs' like just think of sugar-happiness for example
Another picture you may like - remember the updated Kolb Learning Style Inventory? Sooo useful.