Rene Descartes was a 17th century French philosopher and mathematician who is considered the father of modern philosophy. He was a proponent of dualism, which is the view that reality is composed of two fundamentally different substances - mind and matter. According to Descartes, the defining characteristic of matter is that it occupies physical space, while the defining characteristic of the mind is that it thinks. He argued that because the mind does not have physical properties like occupying space, it must be nonphysical in nature. Therefore, Descartes believed that each person is composed of both a physical body and a nonphysical mind or soul. While dualism attempts to explain the interaction between the mind and body, critics argue that it is unclear how a nonphysical mind