Descartes: I am a mind (res cogitans) and a body (res extensa)

Why does Descartes begin this project?

Perception and the evil genius

It is possible that an evil genius has caused all my ideas and perceptions

I cannot be sure this is not so.

\All my ideas and perceptions are dubitable.

I am a mind

If some activity is happening, there must be some entity doing the activity.

I am thinking.

\I am a thing that thinks (res cogitans).

God exists (We’ll look at a version of Descartes’ argument for God’s existence later in the semester)

The material world

I often receive ideas of extended objects.

If I contribute nothing to my having these ideas, I cannot be the cause of these ideas.

This cause must be either God or extended objects.

I am occasionally deceived regarding my ideas of extended objects.

God is not a deceiver.

\These ideas must be caused by extended objects.

\Extended objects must exist.

I have an idea that I am an extended thing.

\I am an extended thing (res extensa)

Knowledge of extended objects (the bee’s wax story)

The body gives us sensory information about the properties of the wax.

This sensory information changes all the time.

\We cannot know through our senses that it is the same wax over time.

\This perception that it is the same wax must come the mind.

\What is being perceived by the mind must be different from the physical properties.

\Objects must have two sorts of qualities.

Mind and body are fundamentally different sorts of stuff

Bodies are the sorts of things that are exclusive to a space, perceived through the senses, etc.

Minds are not exclusive to a space, not perceived by the senses, etc.

\Minds and bodies are fundamentally different sorts of stuff

Interactionism. The pilot and the ship.

I know that minds and bodies interact (when I cut my finger I feel pain).

It does not seem that they should be able to interact

\Nonetheless, there is interaction between the two.