The Brain According to Hippocrates

"Men ought to know that from the brain, and
from the brain only, arise our pleasures, joys,
laughter and jests, as well as our sorrows,
pains, griefs, and tears. Through it, in
particular, we think, see, hear, and distinguish
the ugly from the beautiful, the bad from the good,
the pleasant from the unpleasant...
It is the same thing which makes us mad or
delirious, inspires us with dread and fear,
whether by night or by day, brings
sleeplessness, inopportune mistakes, aimless
anxieties, absent-mindeness, and acts that are
conrtarty to habit. These things that we suffer
all come from the brain, when it is not healthy,
but becomes abnormally hot, cold, moist, or
dry, or suffers any other unnatural affection to
which it was not accustomed. Madness comes
from its moistness. When the brain is
abnormally moist, of necessity it moves, and
when it moves neither sight nor hearing are
still, but we see or hear now one thing and
now another, and the tongue speaks in
accordance with the things seen and heard on
any occasion. But when the brain is still, a man
can think properly."
-From Hippocrates, Vol. 2.