Chapter 7

1. Chapter 7
The Rationalists

2. Descartes
• Cogito ergo suum (Meditations)
• Use rational processes to arrive at 1st
principles
• Logically prove existence of time, space,
God
• analytic geometry

3. Dualism
• Mind/body separate (ala Plato)
• animals have no need for a soul
• Soul is immortal/divine
• Body is a machine (automaton)
– Vivisection
– Clockwork gardens

4. Mechanism
• Deist hypothesis
– “Divine Clockmaker”
– Sets world in motion at creation, then hands off
– Life functions according to natural laws
• Theological problems
– God would have no need of miracles
– Christ not an “intervention”
– Prayers are necessarily ineffective

5. • Calvinist issues
– Descartes believes in free will
– Calvinist predestination
• (the idea that God knows exactly who is going to
hell or to heaven)
– Queen Christina of Sweeden
• Descartes as private tutor
• Dies of pneumonia at 54.

6. Descartes cont...
• Rationalism- Truth comes about through the
careful use of reason.
• Nativism-
• Belief in the existence of innate ideas.
• Contrast with derived ideas, a wax candle of x
number of inches will burn for x number of hours.
• Animal Spirits- means of communication
• Pineal Gland- seat of the soul

7. Descartes cont...
• The reflex

8. Baruch Spinoza
• Jewish
• Free spirit, worked with glass = death
• Double-aspect monism
– Rejects Cartesian dualism
– God as center of everything
• No room for free will: God’s natural laws
determine all

9. Emmanuel Kant
• Middle ground between empiricism and
rationalism
• Analytic a priori (tautology)
• Vs. Synthetic a priori (new truth)
• Innate categories + Experience
• Self-government (Social Psychology)
– Heteronomy (control from outside)
– Autonomy (control from inside)
• Forces in conflict

10. Gottfried Wilhelm Leibniz
(1646_1716)
• Monadology
– Tiny units of consciousness
– Move in preestablished harmony
– Psychophysical parallelism
– Active Mind
– Uniformitarianism: Change is gradual
– Christian Von Wolff: 1st to use “Psychology”

11. Logic and “Truth”
• Rationalists
– necessary truth (a priori)
– must be established before we use sensory
evidence
• self-evident truth (1 + 1 = 2), must believe even
before we can count, basis of math
• Empiricist response
– these truths are tautological (trivial and
circular)
– 1 + 1 = 2 is true cause we made it that way!

12. Logic cont...
• Deduction
– analytic truth
– syllogism
• “Men are mortal. Socrates is a man. Therefore
Socrates is mortal.”
• If premises are true, and argument valid,
then conclusions must be true
• create whole systems of knowledge

13. Logic cont...
• denial of the antecedent
• If x, then y. Not x. Therefore not y
• If you are human, then you are mortal. You are not
human. Therefore you are not mortal.
• affirmation of the consequent
• If x, then y. Y. Therefore x.
• If you are human, then you are mortal. You are
mortal. Therefore you are human.

14. Herbart
• Apperception: Higher mental processes
• Apperceptive Mass
– The collection of all ideas, experiences,
learning that constitutes the mind. This includes
both conscious and unconscious, or aware and
out-of-awareness, if you prefer those terms.

15. Thomas Reid
(1710-1796)
• Common Sense Philosphy, Direct realist
• First Principles: cannot be doubted without
violating common sense
• Hume’s constant conjunction
– We only infer causation,
– But that’s no problem

16. Enfranchising Curiosity