René Descartes Lecture # 3.













Meditation # 5

“Concerning the Essence of Material  Things, and Again Concerning God, That He Exists”

I. Let's talk about two words: ontology and epistemology.

II. Looking back: the thesis of Lecture #1:
Descartes demonstrates that thinking is itself the source of knowledge.  Here (in Meditation #5) Descartes is again looking for answers not to the world outside but to his interior thinking experience.
III.  Armed with his understanding of how to avoid error, the Meditator states his intention as to free himself from the doubts of "a few days ago" and to "see whether anything certain is to be had concerning material things" (87).
(He takes the usual detour!)

IV. The major claim:  In the case of God--and only in the case of God-- Essence implies Existence. This has been called an ontological argument.
A. Since God is perfect and since perfection includes existence, God must exist (89).

B. A good comparison comes from the triangle: Just as the idea of a triangle includes--by definition--3 sides, so also the idea of God includes existence (88).

C. Similarily, the case of a mountain and a valley is different from the concept of God:  it's true that the concept of mountain includes the concept of valley; but it's not true that the conceptual match in this case includes existence (89).
V. Once again, God is not a deceiver, and the Meditator can therefore  have confidence that everything he "clearly and distinctly perceives is necessarily true" (91).




Meditation #6
"Concerning the Existence of Material Things, and the Real Distinction between Mind and Body"


I. First things first: Summary of what the Meditator knows:
A. The Meditator exists and understands his essence (thinking).

B. God exists and is not a deceiver.
    And because God exists and is not a deceiver, the Meditator can work toward setting aside the extravagant doubt of the earlier Meditations.
C. Clarity and distinctness indicate truth.

D. Because his will is free and unlimited (infinite), he can make errors (his volition outruns his judgment).

E. A cause must be adequate to create the effect.

II. What this Meditation will do:
►ask whether the material world exists &
►establish the distinction between mind and body.

III. Does the material world exist?
BTW: The material world is what we all believe in on practical grounds.  
A. The difference between imagination and intellection
1. Compare how you IMAGINE and/or UNDERSTAND
►a triangle
►a chiliagon (1000-sided figure)
►myriagon    (10,000-sided figure)

2. To understand, the mind "turns toward itself" (93).
3. To imagine, the mind "turns toward the body" (93).

4. ►►Imagining is not part of the Meditator's essential identity (essence). See p. 96 for a comparison of thinking on the one hand and imagining/sensing on the other.
B. God has given the Meditator a body in order to experience the material world.  Since God is not a deceiver, the material world exists.

IV. Are the mind and body distinct?  What does that mean?
A.  The mind is a thinking thing.

B. The body is an extended thing.

C. The mind and body are tightly joined (commingled).  The Meditator is present to his body not just as a pilot to a ship but much more closely (98)

D. The body is divisible; the mind is indivisible (101).
V.  Hyperbolical doubts are ludicrous, but human beings are very prone to error and should be on the watch for it.