Descartes

1
Descartes Interactionist Dualism
2
Overview

• Descartes general project
• Argument for dualism
• Explanation of mind/body interaction

3
Descartes General Project

• To secure a firm, certain foundation for the
  sciences
• To prove the existence and goodness of God
• To show how the soul could be immortal

4
The Argument for Dualism

• I have a mind.
• My mind is not my body.
• I have a body.
• Therefore, I have both a mind and a body, which
  are distinct from one another.

5
Argument for Having a Mind

• Descartes considers what it is possible for him
  to doubt, and concludes that it is impossible for
  him to doubt that he thinks.
• He cannot doubt that he thinks because, in
  doubting, he is thinking. It is not possible for
  him to think I am thinking without being right.
• So, he concludes he is a thinking thing, i.e.,
  a mind.

6
Argument for the Existence of Bodies

• It seems to me that there are bodies, and that I
  have one.
• God is too good to allow me to be deceived about
  something so fundamental and important.
• Therefore, there are bodies, and I have one.

7
The Mind is not the Body

1. If the essence of a kind of thing x is y, then
   there could be no x without y. (premise)
2. The essence of body is to occupy space. (premise)
3. For any kind of thing x, if I can imagine an x
   that lacks some property, God can make an x
   without that property. (premise)
4. I can imagine a mind that does not occupy space.
   (premise)
5. Therefore, God can make a mind that does not
   occupy space. (from 3, 4)
6. Therefore, the essence of mind is not to occupy
   space. (from 1, 5)
7. Therefore, the mind is not the body. (from 2, 6)

8
Interaction

• If the mind and body are distinct, we need an
  explanation of how mental and physical events can
  cause one another.
• Descartes tells a story about the mind and the
  body communicating through the pineal gland.
• What problems with this story might there be?

9
Review

• Descartes wants to prove dualism because it
  allows for the immortality of the soul.
• The argument for dualism turns on a perceived
  difference in the essences of mind and body.
• Descartes probably does not solve the problem of
  interaction.