Philosophy of Mind

The contemporary study of mind was given its shape by the seventeenth century philosopher René Descartes. In his Meditations on First Philosophy, Descartes begins with questions about what he can know. He carefully peels away from all that he has taken to be true anything that can be doubted. Descartes claims to reach the limits of doubt when he considers that, although he can doubt the existence of his body, he cannot doubt the existence of his mind. Descartes interestingly (and importantly) conducts the entire of his Meditations in the first person singular. He then presents the conclusion of his doubt thus: "I am, I exist, is necessarily true whenever it is put forward by me or conceived in my mind." (In another of his works, he formulates the conclusion thus: "I think, therefore I am.") This conclusion then launches him onto an examination of what he (this I) is. He considers, and rejects, the suggestion that he is a body (he can, after all, doubt the belief that his body exists). Thinking, however, is "inseparable from me." Descartes concludes that he is a thinking thing, "a thing that doubts, understands, affirms, denies, is willing, is unwilling, and also imagines and has sense perception." Descartes interestingly considers sense perception and points out that, although the objects of sight and sound may not exist, it is still indubitable that one has certain visual and auditory perceptions—that one seems to see and seems to hear. By the end of the Meditations, Descartes has set the stage in the philosophy of mind for the ensuing generations: Mind and body are distinct, each with a different essential nature. The world can seem exactly as it is to a mind, while the bodies to which we take them to correspond may not exist; our world could be the result of the machinations of an evil demon. This is the metaphysical and epistemological position that Descartes bequeathed to future generations of philosophers.

This Cartesian philosophy of mind contains several key aspects. First, it establishes the position known as Cartesian, or substantial, dualism (mind and body are distinct substances). Second, it sets up the possibility of various kinds of skepticism concerning not only the external world, but also the existence of other minds. Third, it sets forth the mind as an arena that is private to the thinker, and—as far as what one seems to perceive—an arena whose contents are infallible and incorrigible. Fourth, it includes in the term thought (Latin cogitatio) not only understanding, willing, imagination, and the like, but also feeling. Fifth, it represents a deliberate rejection of the ancient way of thinking about the soul. Descartes holds that mind is not part of the soul but the "thinking soul in its entirety." The result of this shift is significant. Whereas the ancients allowed souls to all living organisms, with mind restricted to human animals, Descartes holds that the soul or mind is to be found only in human animals. All nonhuman living creatures are, accordingly, mere mechanisms. Interestingly, Descartes views the human body as a mere machine, albeit one to which God has endowed a mind or soul.