René Descartes (1596–1650) is a French scientist/philosopher who proposed a strict split or schism between mental processes and physical abilities.
Descartes hypothesized that the mind and body are separate, but interact with each other. He believed that much human behavior can be explained in mechanical terms, that the mind and the body are separate but interacting entities and that the mind contains innate ideas. With Descartes began comparative-physiological Psychology, stimulus-response Psychology, Phenomenology, and a debate over whether innate ideas exist. Descartes also focused attention on the nature of the relationship between the mind and the body. René Descartes is famous for his exclamation, "I think therefore I am" - Ergo summa cogito. He strengthened the Greek idea about the separation of the mind from the body.