1. The Rationalists: Leibniz Individual Substances
Soazig Le Bihan - University of Montana

2. Outline 1. Introduction 2. Individual Substances and Predication
3. Individual Substances as the fundamental constituents
4. Individual Substances are ``self contained”
5. Individual Substances and their Substantial Form
6. Individual Substances: Independent Mirrors
7. Pre-established Harmony
8. Conclusion
Soazig Le Bihan - University of Montana

3. Review: Leibniz: Rationalism Epistemology:
Granted to the empiricist: empirical knowledge
Against the empiricist: knowledge of eternal truths
Granted to the empiricist: senses as necessary triggers
Against the empiricist: ultimately grounded in pure reason
Compromise, but still eternal truths
Two kinds of truths:
Necessary Truths – Contradiction
Contingent Truths – Sufficient Reason
Contingency exists, not chance
Soazig Le Bihan - University of Montana

4. Soazig Le Bihan - University of Montana
Review:
Leibniz: Theodicy
Starting Point of Leibniz’ philosophy:
God is absolutely perfect
Hence the world is perfect
Perfect in which sense?
God’s Freedom is enlightened, not arbitrary
Perfection = minimal means, maximal complexity
 The best possible world
Challenge: Design a worldview which makes sense of the traditional view of God
Soazig Le Bihan - University of Montana

5. Soazig Le Bihan - University of Montana
Introduction:
Leibniz: Metaphysics
The dangers of the modern reductionism
Descartes: matter = extension and movement
Spinoza: one single substance
 Materialism, necessitarianism, atheism
The conceptual problems within modern reductionism:
Individuation
Freedom with teleology
Moral responsibility
These are the desiderata for a good metaphysical account of the universe for Leibniz
Soazig Le Bihan - University of Montana

6. Outline 1. Introduction 2. Individual Substances and Predication
3. Individual Substances as the fundamental constituents
4. Individual Substances are ``self contained”
5. Individual Substances and their Substantial Form
6. Individual Substances: Independent Mirrors
7. Pre-established Harmony
8. Conclusion
Soazig Le Bihan - University of Montana

7. Individual Substances and Predication
Previous notions of substance
self-sufficient being (Spinoza)
what remains constant under changes (wax)
Substance as the subject of predication
What is predication? Assign a predicate to a subject
Jalisco is a cat
From language to metaphysics
Substances are these beings which are referred to by subjects which cannot be predicated
Which are they?
The fundamental constituents of the world are individual particulars
Soazig Le Bihan - University of Montana

8. Outline 1. Introduction 2. Individual Substances and Predication
3. Individual Substances as the fundamental constituents
4. Individual Substances are ``self contained”
5. Individual Substances and their Substantial Form
6. Individual Substances: Independent Mirrors
7. Pre-established Harmony
8. Conclusion
Soazig Le Bihan - University of Montana

9. Individual Substances as the Fundamental Constituents of the Universe
Taking seriously the notion of substance:
Unique individuals – Principle of Identity of Indiscernibles
Indivisible – ultimate elements
Immutable – except by God
Depend only on God – emanation from God
Unique and stable building blocks of the universe
Soazig Le Bihan - University of Montana

10. Outline 1. Introduction 2. Individual Substances and Predication
3. Individual Substances as the fundamental constituents
4. Individual Substances are ``self contained”
5. Individual Substances and their Substantial Form
6. Individual Substances: Independent Mirrors
7. Pre-established Harmony
8. Conclusion
Soazig Le Bihan - University of Montana

11. Individual Substances as Self-Contained
Requirements for a satisfactory metaphysics:
Fundamental constituents
Recover appearances
Problem: How come that individual substances appear to undergo accidental changes?
Solution: Self-containment
The complete notion of an individual substances contains all the predicates that the substance has had, has and will have
Examples?
Complete notion. In principle, complete comprehension is possible. But what does define an individual substance?
Soazig Le Bihan - University of Montana

12. Outline 1. Introduction 2. Individual Substances and Predication
3. Individual Substances as the fundamental constituents
4. Individual Substances are ``self contained”
5. Individual Substances and their Substantial Form
6. Individual Substances: Independent Mirrors
7. Pre-established Harmony
8. Conclusion
Soazig Le Bihan - University of Montana

13. Individual Substances defined by their Substantial Form
The old notion of substantial form:
Crucial notion for Aristotle and the Scholastics
Example: the socrates-hood of Socrates
 What makes something what it is
Despised by modern philosopher: vacuous explanation
Defended by Leibniz for metaphysics:
vacuous explanation in physics - clock
necessary in metaphysics – unity and individuation
Every individual substance has an intrinsic principle of unity and individuation.
Soazig Le Bihan - University of Montana

14. Outline 1. Introduction 2. Individual Substances and Predication
3. Individual Substances as the fundamental constituents
4. Individual Substances are ``self contained”
5. Individual Substances and their Substantial Form
6. Individual Substances: Independent Mirrors
7. Pre-established Harmony
8. Conclusion
Soazig Le Bihan - University of Montana

15. Individual Substances as Independent Mirrors of the Universe
Requirements for a satisfactory metaphysics
Problem: The appearance that each substance interact with the external world?
Solution: Mirrors of the Universe
Each individual substance expresses the entirety of the universe from its own perspective
Analogy: movie theater
So: each substance actively unfold itself, i.e. expresses the entire universe from its unique perspective.
Pb: why are our movies consistent with one another?
Soazig Le Bihan - University of Montana

16. Outline 1. Introduction 2. Individual Substances and Predication
3. Individual Substances as the fundamental constituents
4. Individual Substances are ``self contained”
5. Individual Substances and their Substantial Form
6. Individual Substances: Independent Mirrors
7. Pre-established Harmony
8. Conclusion
Soazig Le Bihan - University of Montana

17. Pre-established Harmony
Requirements for a satisfactory metaphysics
Problem: Correlations between our world – causal connections
Are we watching movies independently or acting in the same movie?
Solution: Pre-established Harmony
- Correlations: direct causal influence vs. synchronization
- Super synchronization by God’s decree
Analogy
Appearance of causality:
Causality is an illusion
Causal Influences: restriction/expansion of the domain of expression
Soazig Le Bihan - University of Montana

18. Outline 1. Introduction 2. Individual Substances and Predication
3. Individual Substances as the fundamental constituents
4. Individual Substances are ``self contained”
5. Individual Substances and their Substantial Form
6. Individual Substances: Independent Mirrors
7. Pre-established Harmony
8. Conclusion
Soazig Le Bihan - University of Montana

19. Conclusion on Leibniz’ Metaphysics
Fundamental Level: Independent, self-contained, unique, indivisible and immutable substances emanating from God:
Each possesses an intrinsic principle of unity
Each expresses the entire universe from its unique perspective
All perspectives are synchronized
Phenomenal Level:
Well grounded illusion of a causal order between interacting systems in a common, material world.
Soazig Le Bihan - University of Montana