The word _humour_ is one which has changed its meaning very much in the course of its history. It comes to us from the Latin word _humor_, which means a "fluid" or "liquid." By "humour" we now mean either "temper," as when we speak of being in a "good" or "bad" humour, or that quality in a person which makes him very quick to find "fun" in things. And from the first meaning of "temper" we have the verb "to humour," by which we mean to give in to or indulge a person's whims. But in the Middle Ages "humour" was a word used by writers on philosophy to describe the four liquids which they believed (like the Greek philosophers) that the human body contained. These four "humours" were blood, phlegm, yellow bile (or choler), and black bile (or melancholy). According to the balance of these humours a man's character showed itself. From this belief we get the adjectives--which we still use without any thought of their origin--_sanguine_ ("hopeful"), _phlegmatic_ ("indifferent and not easily excited"), _choleric_ ("easily roused to anger"), and _melancholy_ ("inclined to sadness"). A person had these various temperaments according as the amount of blood, phlegm, yellow or black bile was uppermost in his composition. From the idea that having too much of any of the "humours" would make a person diseased or odd in character, we got the use of the word _humours_ to describe odd and queer things; and from this it came to have its modern meaning, which takes us very far from the original Latin. It was from this same curious idea of the formation of the human body that we get two different uses of the word _temper_. _Temper_ was originally the word used to describe the right mixture of the four "humours." From this we got the words _good-tempered_ and _bad-tempered_. Perhaps because it is natural to notice more when people are bad-tempered rather than good, not more than a hundred years ago the word _temper_ came to mean in one use "bad temper." For this is what we mean when we say we "give way to temper." But we have the original sense of "good temper" in the expression to "keep one's temper." So here we have the same word meaning two opposite things.