The Rationalists: Descartes
The Cartesian Doubt
Soazig Le Bihan - University of
Montana
1
Descartes: Life and Works
Life:
1. Brilliant but not complaisant student
2. “Bene vixit qui bene latuit”
3. Dies in Sweden (Queen Christina)
Interests: 1. Not Aristotelian philosophy
2. New system
3. Pragmatic matters
Works:
1. The World – physics
2. Discourse – Meditations – Principles
3. Passions of the soul and letters to Elizabeth
Soazig Le Bihan - University of
Montana
2
The Meditations: Aim and Method
Topic and Style: - Topic: Metaphysics
- Style: Analytic (by contrast to
synthetic)
Aims: - Avowed: Proof of the existence of God and
separation of the soul from the body
- Ultimate: Give a definite foundation to the new
science
Soazig Le Bihan - University of
Montana
3
The Meditations: Aim and Method
Method: The Rational Stance
- Defense of the use of reason for religious matters
- Proper method: demonstration and certainty
Two enemies:
- Prejudices
- Senses
Soazig Le Bihan - University of
Montana
4
The Cartesian Doubt:
What is it and what is it for?
General Project:
- General destruction of all his opinions – Why? No firm
foundation
- “to raze everything to the ground and begin again from the
original foundations” in order to build firm science
The Cartesian Doubt:
- Universal
- Hyperbolic
- Radical
- Methodological
Soazig Le Bihan - University of
Montana
5
The Cartesian Doubt:
The Senses
Why the senses? One of the roots of knowledge
Arguments:
- The traditional argument is not enough
- Dream argument: no sufficient criterion to tell that we are
not dreaming.
Result: are doubtful (and hence taken as false):
- The existence of the external world
- The existence of my own body
Soazig Le Bihan - University of
Montana
6
The Cartesian Doubt:
Mathematical Notions
The most fundamental constituents: Anything left?
Arguments: Analogy with painting
Painting:
Dream
Components:
body parts
Most General:
colors
Soazig Le Bihan - University of
Montana
Imagination /
bodies
corporeal nature
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The Cartesian Doubt:
The Evil Genius
Would it be possible that I be deceived concerning math?:
 Deceiving God?
The case of the Atheist – even less reason to believe he or she
can attain firm knowledge
Conclusion – Not a single part of the entire body of
knowledge seems to be indubitable
Soazig Le Bihan - University of
Montana
8
The Cartesian Doubt:
Conclusion
The danger of habits: doubting is not easy
The power of will: focus and resolution
Soazig Le Bihan - University of
Montana
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