THE BRAIN – A PLATONIC VIEW

Aristotle’s teacher, Plato, reasoned that the mind had to exist inside the brain because of geometry and pure logic. The brain was round, he said, and close to the perfect roundness of the sphere. It also inhabited the part of the human body closest to heaven.

The idea that the mind survives the body's death appears quite ancient. Burial sites from 100,000 years ago reveal bodies interred with tools and food, possibly to help on journeys in the afterlife. Cave art possibly depicts spirit worlds.

Plato and other Greek philosophers theorized about the existence of a force that kept people alive and left them at death. They called this force psyche, or soul, and several said it resided in the brain. Some split the soul into three spirits. Humans and all living creatures took in life-giving essence from pneuma, or air. As pneuma moved through the body, it changed in ways that animated and strengthened its host. Digested food provided energy for the liver, where the pneuma became “natural spirit.” This spirit traveled to the heart to become the “vital spirit.” Then it traveled to the brain, where it transformed into the “animal spirit” that creates the conscious mind. Plato considered the soul that resides in the brain to be immortal, surviving the death of the body.