Men ought to know that from the brain, and from the brain only, arise our pleasures, joy, laughter and jests, as well as our sorrows, pain, grief and tear. Through it, in particular, we think, see, hear, and distinguish the ugly from the beautiful, the bad from the good, and 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-mindedness, and acts that are contrary to habit. These things that we suffer all come from the brain, when it is 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, be we see or hear now one things seen and heard on any occasion. But all the time the brain is still, a man can think properly.