Descartes1596 - 1650

• Historical Context• Epistemology vs. Metaphysics• Subjective vs. Objective• Arguments

- Dreaming- Evil Demon- Cogito- The Wax

• Substance Dualism• The Mind/Body Problem• The Body Problem

Descartes1596 - 1650

• Philosophy as Science

• The I Language

Metaphysics? Or Epistemology?

Subjective vs. Objective

The Arguments

• Everyday Mistake: Sensory Doubt• Dreaming Argument: Now Dreaming Doubt• Evil Demon Argument: Always Dreaming

Doubt

Dreaming Argument P1: I often have perceptions while I am dreaming which are very much like the [sensory] ones I have while awake.P2: These perceptions I have while dreaming are false.P3: I can be wrong (even though it seems as though I am certain) about my perceptions while dreaming.P4: There are no definite signs to distinguish dream experience from waking experience.P5: I can be wrong (even though it seems as though I am certain) about my perceptions while awake.C: It is possible that I am dreaming right now and that my perceptions are false.

Evil Demon Argument

Urbain Grandier Asmodai Sister Jeanne of the Angels French Catholic Priest Evil Demon Mother Superior: Convent

of Loudun

Nuns accusation & Trial: 1632Descartes’ Meditations: 1641 Latin Translation; 1647 French Translation

Pact with the Devil

The Cogito

If I am thinking then I necessarily exist.

Wax

• Primary vs. Secondary QualitiesNecessary/Contingent

Mind/Body

• Primary Qualities

Necessary

Mind: Thought Body: Extension

• Dualism

Substance (Cartesian) Dualism: two ultimate and irreducible kinds of reality

Mind/Body Problem How to connect the subjective mental to the

objective physical

• How does one causally interact the other?

Pineal Gland

Interactionist: mind/body causally act on each other via pineal gland

The Body Problem

• What does it mean to be physical?Descartes: physical matter “that which has extension in space”Electrons: point-particles with no extension (lacking a determinate spatial position)

• Category of physical: rocks, trees, subatomic particles: quarks, gluons, leptons, dark matter

• Category of non-physical: mental, beliefs, desires

Ghosts

1. They can pass through walls without disturbing the wall.Neutrinos: can pass through matter without disturbing it.

2. They have no mass.Photons have no [rest] mass.

3. Take up no space?Point particles don’t take up space.