What are the four humors and what do they do?

Search: the four bile

Why: Marcel said The Smiths are great because everyone needs a little melancholy in his life (even though I called them "pretty goddamn melodramatic," not melancholy).

That word comes from Greek melas, "black" + khole "bile."

Medieval physiology attributed depression to excess of "black bile," a secretion of the spleen and one of the body's four "humors."

(Also, the name Chloe comes from the word for the greenish-yellow color of bile, too.)

Answer: First, they are outlined the Hippocratic Corpus as a way to balance bodily fluids.

They are!

1. Yellow bile! (gall bladder)
   
2. Black bile! (spleen)
   
3. Phlegm! (brain/lungs)
   
4. Blood! (liver)
   

Each is associated with a season and a quality:

• Yellow bile: Summer; hot & dry
• Black bile: Autumn; cold & dry
• Phlegm: Winter; cold & moist
• Blood: Spring; hot & moist
  

They are also associated with elements and hypochondriac diseases:

• Yellow bile: Fire; too much fire made a person choleric
• Black bile: Earth; too much earth made him melancholic
• Phlegm: Water; too much water, phlegmatic
• Blood: Air; too much air, sanguine

Each had a corresponding body type and complexion:

• Yellow bile: Red-haired, thin
• Black bile: Sallow, thin
• Phlegm: Corpulent
• Blood: Red-cheeked, corpulent
  

and a temperament or personality:

• Yellow bile: Ambitious, bad tempered, vengeful violent
• Black bile: Despondent, introspective, irritable, sentimental, sleepless
• Phlegm: Calm, cowardly, unemotional, pallid, sluggish
• Blood: Amorous, generous, happy, hopeful, responsible
  

and also:

Source: About.com/ancienthistory, Wikipedia,

The More You Know: They also have suggested modern equivalents, as well as Myers-Briggs types:

• Yellow bile: Idealist; NF (intuition-feeling)
• Black bile: Guardian; SJ (sensing-judgment)
• Phlegm: Rational; NT (intuition-thinking)
• Blood: Artisan; SP (sensing-perception)

Which one are you? (I am phlegm.)