5 Leibniz (1646-1716): Metaphysics

1. 5Leibniz (1646-1716): Metaphysics

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3. Introduction • A good introduction to Leibniz: Jolley N. (2005). Leibniz. Routledge • Leibniz’s New Essaysfree at: http://www.earlymoderntexts.com/f_leibniz.html

4. The only published works of Leibniz attempts to reconcile philosophy with Christian doctrine. His most famous published book, Theodicy, promised an explanation of the existence of evil in a world created by a being who is perfectly good. • Leibniz was also a great logician. He considered the theory of truth, not religion, as the starting-point of philosophy.

5. Main (philosophical) works Because of his diplomatic engagements he didn’t published a systematic work like other contemporary philosophers (e.g.: Descartes, Locke, …). He published only one book. Other books have been published after his dead. • Lot of letters/correspondences with major philosophers (Arnauld, Malbranche,…)

6. BOOKS: Discourseon Metaphysics (composed in 1686). Each substance, is like a whole world and like a mirror of God. New Essays on Human Understanding (composed in 1703-5). He didn’t publish it because Locke died in the autumn of 1704. Locke’s essays have been published in 1690. This is known to be one of the best debate between a rationalist and empiricist conception.

7. Essay on Theodicity (= the justice of God. published in 1710). The only book he published. Defence of the justice of God who created the best of the possible worlds. It is an attempt to reconcile the existence of evil in the world with God’s benevolent nature. Monadology(composed 1714). Monads are spiritual substances created by God. They are the basic building block of nature.

8. God’s Will and Intellect • Main Thesis God’s mind consists in a will and intellect, like the human mind. • Vs. Descartes Descartes argued that it would be a contradiction to suppose that God’s will is determined to act in one way or another (cf. Reply to Sixth Objections, Objection 6).

9. Descartes: God doesn’t act out of a prior conception of what is good or bad. God’s acts of will determine what is good or bad. This allowed Descartes to explain God’s freedom in terms of the indifference of God’s will.

10. Leibniz considered this view to be dangerous, in that it threatened to make values relative. If what is good or bad depends on God’s arbitrary whish, what we now call bad could just as well be good if God decided so. • Leibniz proposed instead that God’s intellect determines his will. God does that which s/he considers to be the best.

11. God’s acts are timeless (i.e. they don’t take place in time) One of Leibniz’s most basic general metaphysical principles, the “principle of sufficient reason”, is based on this supposition. Anything that exists is due to the activity of God, and God always acts for the reason that it is the best.

12. Principle of Sufficient Reason For anything that exists, there is a reason sufficient to determine God’s will to bring it about, i.e., the reason that its existence would be for the best.

13. Ontological Economy God’s actions follow a principle of economy. God acts according to the most economical means to bring about the most abundant ends. Analogy: An architect, for example, will use his location and the funds set aside for a building in the most advantageous manner, allowing nothing improper or lacking in the beauty of which it is capable.

14. God’s economy is carried out through the use of general rules governing creation. Some of these rules are discoverable by us humans, and we call them laws of nature. Others are hidden. These are in play when there is a miracle which violates a law of nature. Miracles are not irregular events but conform to more general regularities.

15. The Metaphysics of Substances • Critique of Descartes A substance must be a genuine unity. In Descartes the universe is composed of two created substances: (i) mind whose essence is to think, and (ii) body whose essence is to be extended (three- dimensional)

16. Body as it is conceived by Descartes doesn’t fit the bill of being a substance. Descartes’ main problem is that he neglected the Aristotelian tradition …

17. Aristotle’s two tests for being a substance 1. The linguistic test Substances are the ultimate subject of predication. Socrates passes the test since we can predicate many things of him, while Socrates can be predicated to nothing. The name “Socrates” can appear only in subject position (cf. singular vs. general terms). A substance must be something designated by a singular term.

18. 2. The metaphysics test Substances are substrata of things. The most distinctive mark of a substance is what remains numerically the same (cf. Aristotle’s essentialism). Numerical identity vs. Qualitative identity Socrates the baby is 2 feet tall while Socrates the adult is 6 feet tall, yet Socrates is one and the same individual. Socrates numerical identity cannot correspond to his body (resextensa).

19. Leibniz’s argument against Descartes’ doctrine of extended substances (res extensa) 1. No aggregate is an ultimate subject of predication 2. An entity whose essence is extension is an aggregate 3. Therefore, no entity whose essence is extension is an ultimate subject of predication. Since being an ultimate subject of predication is a necessary condition for being a substance, no entity whose essence is extension is, pace Descartes, a substance.

20. Any Cartesian body is composed of other bodies Nowhere in Descartes’ theory of the physical world we come to entities which are not themselves aggregates. Leibniz introduces a stipulative definition of “substance”: “substance” =df. “That which has a true unity” Therefore, any entity whose essence is extension is not a substance since it lacks genuine unity.

21. The Logicist Strategy • All true predication has some foundation in the nature of things. When the predicate is not expressly included in the subject, it must be virtually included in it (‘in esse’: the predicate is in the subject). The subject term must always involve that of the predicate. So one who perfectly understands the subject notion would also see that the predicate belongs to it.

22. Theconcept-containment theory of truth In all true affirmative propositions, necessary or contingent, universal or singular, the notion of the predicate is always in some way included in that of a subject …-- or I don’t know what truth is. (Leibniz, Philosophical Texts, Oxford UP 1998: 11-2) • Proper name: it’s not an arbitrary simple tag. It expresses a concept like a general term (e.g. “lemon”, “gold”). Hence: “Cesar crossed the Rubicon” is true because the predicate “crossed the Rubicon” is contained in the subject concept expressed by the name “Cesar”.

23. Individual substances have complete concepts. If one were to know the complete concept of Alexander, one would ipso facto also know everything there was to be known about the universe. All relational truths about individual substances can be deduced from non-relational truths about those substances. (e.g.: “Mary is Tim’s sister”; being Tim’s sister is contained in Mary’s substance …) Every substance expresses the universe. But only God can recognize the whole concept.

24. Causality • The critique of the influx model Influx model Causal interaction about substances in the world must be understood as involving a process of contagion. When a substance A causes a change in substance B, A infects B with one of it properties (i.e. by an instance of a property). E.g.: when the kettle boils the gas infects the water within the kettle.

25. The influx model of causality is (for Leibniz) incoherent for it rests on the metaphysical fiction that accidents can become detached from their own substance and move to other substances. • There is no causal interaction between substances. Leibniz claims that monads (the ultimate substances) have no windows. Pre-established harmony. • Causality of creatures is modeled on Divine creation. • Created substances are mirrors of God.

26. Ontology • Createdsubstances: 1. they are genuine unities 2. they are genuinely active and causally self-sufficient 3. they express the entire universe (and thus reflect the divine perfection of omniscience) In all these ways substances are mirrors of God (Cf. Genesis: God made man in his own image).

27. Leibniz abandons the Aristotelian ontology of corporeal substances. The doctrine of monads is a form of idealism. • Appearance vs. Reality Emphasis (already in Descartes) on the fact that appearances are misleading. The physical world is, strictly speaking, deprived of sensory qualities (e.g. colors, odors and taste…)

28. Monads • Monad (from the Greek meaning unity) = a simple, immaterial, soul like, substance endowed with perception and appetition. • Appetition = the endeavor or striving in a monad by virtue of which it passes from one perceptual state to its successor. Appetition explains monad dynamicity. So simple substances/monads can be sources of activity. • Atomism: Monads are the true atoms of nature.

29. Since nothing purely material can be indivisible, monads cannot be like atoms traditionally conceived. • Monads qua simple are without parts. Thus they cannot be corporeal. They must be immaterial. • Monads are indestructible, for destruction consists in decomposition which is a dissolution of a thing into its composing parts (see unity of substance).

30. Monads can begin (and end) only by a miraculous act of creation (or annihilation). • If monads are simple, immaterial and indestructible, then the building block of the universe share certain properties with God (they are the mirror of God). • The building blocks of the universe are all mental or soul like entities. They are spiritual atoms.

31. Monads are windowless: So neither substance nor accident can come into a monad from outside. • All monads express (perceive) the entire universe. Yet no two monads are exactly alike. They have different points of view. • Differences in points of view: to be analyzed in term of the distribution of clarity and distinctness over their perceptual states.

32. Identity of Indiscernible: Leibniz Law • The notion of point of view allows Leibniz to accept the principle of the Identity of Indiscernibles (sometimes also known as Leibniz law). If, for every property F, object x has F if and only if object y has F, then x is identical to y. F(Fx  Fy)  x=y

33. Converse of the Principle: the Indiscernibility of Identicals If x is the same as y, then x and y have all the properties/qualities in common. x=y  F(Fx  Fy) Sometimes the conjunction of both principles, rather than the Principle by itself, is known as Leibniz's Law. x = y Fx  Fy

34. The hierarchy of monads. 1. God is on top by virtue of possessing perceptions that are clear and distinct. 2. Human minds are lower. They are high quality monads by virtue of (i) possessing reason allowing them to entertain eternal truth of logic and mathematics and (ii) self-consciousness: the ability to say “I”. 3. At the bottom we have bare monads. They have perceptual states but they are extremely confused and obscure. They have no consciousness.

35. Bodies • Given Leibniz’s ontology of monads (immaterial substances); what about bodies or physical objects? Contemporary materialists can adopt an eliminativist approach: there is nothing but physical substances and, strictly speaking, there are no such thing as mental states. Another alternative is to claim that mental states are reducible to state of the body/brain.

36. Leibniz’s reductionism Reductionism about bodies. Does Leibniz anticipate Berkeley’s phenomenalist account (esse es percipy), i.e. the view that each soul or monad is somewhat watching a private film? When we say “Socrates is sitting” we mean that the concept Socrates is appearing to us and other who are concerned. “Fa” can be translated into “It appears to me that Fa”

37. Leibniz may not be a phenomenalist insofar as he claims that bodies result from monads, i.e. that bodies are aggregate that result from monads. • “Result from monad”: what does it mean? Resulting. What it is not: 1. It cannot be a causal relation, since monads have only internal causation. Monads produce their perceptual state by means of striving or appetition, but they don’t produce bodies.

38. 2. The resulting relation cannot be one of whole to parts. Monads have no parts and bodies are not composed of monads. 3. Resulting is not identity. Leibniz doesn’t say that bodies are identical with aggregates of monads. 4. Resulting is not supervenience, i.e. bodies do not supervene on certain sets of monads as the goodness of an apple supervenes on some of its physical properties.

39. Resulting = monads express bodies We can correctly say that bodies are founded in monads, but not that monads are founded in bodies. Each body stands in a privileged relation to a subset of the totality of monads which has the job of well-founding it.

40. Leibniz provides metaphysical foundations for its physics. The physical forces in bodies (e.g. kinetic energy) are grounded in the primitive forces of monads, i.e. appetition. • Leibniz is a reductionist in a looser sense. He claims that there really are bodies (such as tables and stones). Yet facts about bodies can in principle be derived from facts about monads, the only true substances in the universe.

41. Is Leibniz inconsistent in claiming that the only substances of the universe are monads and in also talking about corporeal objects? Leibniz seems to embrace both forms of idealism and form of corporeal substances. The fact that Leibniz continues to speak of corporeal substances doesn’t necessarily mean that he is not committed to idealism. He may be seen as offering a form of reductionism.

42. The theory of the substantial bond (vinculum substantiale) It is something above monads which unifies the monads as an organism into a substantial whole. An obscure theory (it emerged lately in Leibniz’s work), which should explain the unity of organisms: i.e. the difficulty of joining different simple substances or monads existing in our body to make a unique, to make us.