What Was It Like to Be Awake?

In school Descartes studied mathematics and physics. He joined up with a group of Dutch mercenaries during the Thirty Years War where he fought in the Battle of the White Mountain. It was right after this battle that Descartes claims he received a number of visions. To escape the cold he locked himself in a small room with a little furnace. During the night he had these weird visions that sometimes included loud sounds.