Descartes and Dualism
"I think therefore I am," the well known quote of Rene Descartes, is the basis of his theory known as dualism. The intermingling of mind and body or res extensa (extended substance) and res cogitans (thinking substance) displays Descartes' ideas of a "genuine human being" (Cottingham 7). Known as the father of modern philosophy, Descartes realized that one could not analyze a problem simply on the common sense level, but that one must "probe to the micro-level" (Cottingham 4).
Through his technique of doubting everything which he believed to exist and establishing a new philosophy, Descartes discovered that without a doubt, the only thing he could truly believe to exist was his own mind. He then supposed that a demon was deceiving him by causing him to believe that which he saw. With this idea, he concluded "all external things are merely the delusions of dreams" (Descartes' Meditations as cited in Cottingham 23) which the demon has devised. By being able to convince himself of ideas and by being able to be deceived by the demon, Descartes could assume that he existed. He also came to the conclusion that if he were to cease from thinking, he would cease to exist entirely (Cottingham 28).
"I regard the body as a machine so built and put together...that still, although it had no mind, it would not fail to move" (Descartes' Meditations as cited in Jones). Descartes' idea of the body being totally independent of the mind is known as the mechanistic view. Descartes explains this concept by offering the explanation that spirits enter the brain cavities, proceed to the nerves, and change the shapes of the muscles in order for movements of the body to take place. The mechanistic view compares the body to several different mechanical objects including clocks and fountains. However, Descartes found that the human body was in every way better built than any mechanism a human could devise (Shapin 158).
"There is a vast difference between the mind and the body, in that the body...is always divisible, while the mind is completely indivisible" (Descartes' Meditations as cited in Strathern 67). Although Descartes claimed that the mind and body were totally separate beings, he also found that they were closely intertwined. Descartes concluded that because a body part could be removed without taking away from the mind, the body was a separate being (Cottingham 36). The interdependence of the mind and body was what Descartes considered a human being; the mind and body formed a unit. Descartes found that because you sense things occurring to the body through the mind, then if the body and mind were not intertwined, one would not have any feelings in the body. These "feelings" in the body are what Descartes called "confused thoughts" (Cottingham 40) because they could not be explained through equations or logical connections. The confirmation for the idea that the mind and body were closely connected was the fact that one can never separate from his body, and can feel and sense things only through his own body.
Descartes' philosophy "transformed European thought" (Strathern 55) by causing people to gradually reject the Aristotelian views of the mind and body. Although later philosophers including Locke, Berkeley, and Hume rejected Descartes' ideas, other philosophers such as Regis and Malebranche expanded and improved upon Descartes' philosophy to form Cartesianism.
Works Cited
Cottingham, John. Descartes. NY: Routledge, 1999.
Jones, Stephen. Extracts From Rene Descartes' philosophical analysis of the Mind and the Brain: website.
Shapin, Steven. The Scientific Revolution. Chicago: University of Chicago Press, 1998.
Strathern, Paul. Descartes in 90 Minutes. Chicago: Ivan R. Dee Inc., 1996. Partner sites: French Bulldog, Spanish school in Quito, and Wedding Speeches