René Descartes (1596-1650) was a philosopher, mathematician, and writer. He was born in France and spent much of his life in the Dutch Republic.

Descartes referred to the pineal gland as the "principal seat of the soul." In The Broom of the System, Stonecipher Beadsman mentions that Descartes thought that "the pineal gland was where mind met body" while talking to Lenore.