Ron Yezzi

Gottfried Wilhelm Leibniz (1646 - 1716)

A. Life

1. Leibniz was a brilliant student with an interest in, and mastery of, just about every area of human knowledge.

2. He traveled widely and met many of the great thinkers of the day.

3. He held various diplomatic posts and also held positions as an archivist.

4. He preferred promotion of grand social projects of unification to an intellectual career in philosophy.

        a. He tried to reconcile Protestantism with Catholicism--through intellectual effort and political action.

        b. He sought to serve the common interests of all the German states, although his diplomatic posts were associated with particular states.

        c. He promoted development of scientific societies in various nations.

        d. He never produced a systematic work expounding his own philosophy.

5. Independently of Newton, he developed the differential calculus and integral calculus.

        a. The development took place in the mid-1670s with publication in the mid-1680s.

        b. Since Newton developed the calculus in 1666 but did not publish until 1692, a bitter feud developed between the two over who was the discoverer of the calculus.

6. Although he was at one time one of the best known men of his time, he died in obscurity.

7. Leibniz' philosophical writings are scattered over a multitude of articles and papers, with only one longer work, the Theodicy.

B. Philosophical Significance

1. Leibniz developed a solution to the mind-body problem now known as psycho-physical parallelism.

2. He made a number of important distinctions that have become part of the philosophical literature--truths of reason, truths of fact, the identity of indiscernibles, the principle of sufficient reason, monads.

3. He is associated with the famous claim that we exist "in the best of all possible worlds."

C. Major Philosophical Positions

1. Principle of Sufficient Reason – For anything that exists or for any change that occurs, there must be a reason present and sufficiently powerful to produce it.

        a. This Principle applies as well to the existence of the universe, cause-effect relationships, and choices.

2. Principle of the Identity of Indiscernibles – For there to be two substances, there must be some difference in their properties.

        a. No two things can be exactly alike.

3. Distinction between Necessary and Contingents Truths (or the Distinction between Truths of Reason and Truths of Fact – Necessary truths are ones whose denial entail a contradiction; Contingent truths are ones whose denial does not entail a contradiction.

        a. Truth of Fact: I am in a room right now; but my not being in the room is not a contradiction.

4. The Basic Nature of Monads

        a. The world consists of a plurality of simple, wholly independent, indivisible substances, or monads, that are psychic entities with a structure indicative of some purpose.

        b. Every monad is unique, that is, is different from every other one (as required by the Principle of the Identity of Indiscernibles).

        c.  Monads possess properties and relations; but these change due solely to internal principles.

        d. The structure of a monad constitutes an entelechy, or substantial form, sufficient to direct its internal development.

        e. Compound substances consisting of an aggregate of monads are directed by dominant monads. For example, an organic being is a compound substance.

        f. Monads are created by God.

5. Psychic States of Monads

          a. Bare perceptions (which Leibniz likens to being in a state of stupor)

        b. Distinct perceptions

        c. Memories

        d. Apperception (consciousness)

        e. These psychic states are then attributable to different types of monads.

6. Types of Monads

        a. Bare monads [which Leibniz also refers to at times as material souls, although he also sometimes does not like to use the term "soul" in connection with them (See text, p. 237)]

                1) Bare monads are the entelechies associated with material bodies.

                2) They exhibit only the lowest psychic state, perception.

        b. Animal Souls

                1) These are the monads associated with animals.

                2) They add distinct perceptions and memories as psychic states. (Animals have memories in the sense that, for example, a dog that has been hit by a stick in the past will recoil at the mere sight of someone approaching with a stick.)

        c. Minds (rational souls)

                1) They possess consciousness—including the capacities for reasoning, reflection, and self-hood (recognition of an "I"). So this is the human level of existence.

7. Monads and Pre-established Harmony

        a. Monads are described as being "windowless," since they change entirely due to an internal principle; so they do not in any way interact with one another. "Moreover, every substance is like a complete world and like a mirror of God or of the whole universe, which each one expresses in its own way, . . . "("Discourse on Metaphysics, par. 9)

        b. Accordingly, twenty persons in a classroom are not interacting with one another as they seem to be listening to whoever is speaking and to discuss issues back and forth; each is a separate universe functioning according to each one’s own internal principle.

        c. But there is a perfect, pre-established harmony, established by God, in nature such that the development of these independent monads is coordinated together. So what one person says and another person hears are perfectly coordinated so that the particular speaking and hearing occur at precisely the same time in the development of each person’s own being.

8. Rejection of Materialism

        a. Leibniz’ rejection of materialism required an explanation of the need for monads rather than acceptance of the independent existence of any brute matter. Following his mathematical inclinations (somewhat like dividing a line), he seems to focus, in particular, on the infinite divisibility of matter, or bodies, as preventing their independent existence.

        b. "I perceived that it is impossible to find the principles of a true unity in matter alone, or in what is only passive, since everything in it is only a collection or aggregation of parts to infinity" (from "A New System of the Nature and Communication of Substances," see text, p. 230).

        c. In a work entitled "On Nature Itself, or On the Inherent Force and Actions of Created Things," he makes a distinction between "primary matter," or "mass," and "substantial forms" (which also are known as entelechies). (In the "New System" essay, he also refers to "material mass.") This distinction suggests that Leibniz’ claiming that material bodies cannot exist in themselves but require monads is akin to Aristotle’s description of natural substances requiring both matter and form—RY.

        d. In the "Discourse on Metaphysics" (par. 12), he says, ". . . the nature of the body does not consist merely in extension, that is, in size, shape, and motion, but that we must necessarily recognize in body something related to souls, something we commonly call substantial form, even though it makes no change in the phenomena, any more than do the soul of animals, if they have any."

        e. Leibniz’ position on matter here shows clearly his opposition to materialism; but it is worrisome in terms of Ockham’s razor: Do not multiply entities beyond necessity.—RY

9. Mind and Body

        a. Given Leibniz’ insistence on the existence of monads, psychic entities, to explain the existence of material bodies, we would expect that there is no separation of mind and body—that is, we would expect that there is no matter as such, but only different varieties of psychic entities. This is not the way Leibniz writes however. He seems to treat the mind and body as separate entities, as persons ordinarily might separate them. (That is why I like to think of his talking of mind and body as separating mental monads from material monads.—RY)

                1) The separation of mind and body could be taken simply as an acceptance of common usage rather than a metaphysical separation; given its importance however, I think that Leibniz would have to make an explicit disclaimer here--RY.

        b. Monadology (par. 78): "These principles have given me a method for explaining naturally the union or, better, the conformity of the soul and the organic body. The soul follows its own laws, and the body its own likewise, and they agree with each other by virtue of the harmony pre-established between all substances, since they are representations of one and the same universe."

        c. Monadology (par. 81): "According to this system, bodies act as if there were no souls (though this is impossible); and souls act as if there were no bodies; and both act as if each influenced the other."

        d. Monadology (par. 79): "Souls act according to the laws of final causes, through appetitions, ends, and means. Bodies act according to the laws of efficient causes or of motions. And these two kingdoms, that of efficient causes and that of final causes are in harmony with each other."

                1) His explanation of body being governed by efficient causes raises questions about the formlessness of matter in his rejection of materialism. The chain of efficient causes, governed by the Principle of Sufficient Reason, would seem to involve a highly structured sequence of events rather than formless matter.--RY

        e. Thus there is no relationship of any sort between the physical act of my opening a door and my mental decision and awareness about opening a door; due to the pre-established harmony, however, the physical act and the mental awareness just happen to occur at the same time.

        f. Leibniz' position here on the mind and body gives rise to psycho-physical parallelism―that is, the position that mind and body do not interact at all but remain perfectly coordinated together in parallel sequences through a pre-established harmony.

10. God

        a. God is a perfect being and therefore always acts in the best possible way; hence God has chosen this as the best of all possible worlds.

        b. Three proofs of God’s existence

                1) Leibniz tends to treat proofs of God’s existence somewhat casually. That is to say, he does not treat the proofs as being of fundamental importance, as if God’s existence is so obvious that no great stress on the proofs is necessary. So I will just allude to the proofs briefly here.—RY

                2) Perfection requires existence (although he does mention a problem he has with the way Descartes stated the proof—RY).

                3) Since everything that exists requires a sufficient reason to exist, God is necessary as the sufficient reason for the existence of the universe.

                4) God is necessary for the existence of the pre-established harmony.

        c. Contrary to Spinoza, Leibniz argues for both the inherent goodness of nature as a whole and the importance of final causes. Without them, we destroy God's goodness, love, and glory.

        d. God acts freely but also can act in only one way—since there is just one way that expresses perfection. This is not in any sense a restriction on God—either with respect to freedom, omnipotence, or omniscience—because God wills to do exactly what expresses perfection.

                    1) For any choice, there must be a sufficient reason for it. That is, there are no entirely spontaneous choices. So God has a sufficient reason, namely, the requirements of perfection, that explain and necessitate God’s choices.

                2) So something is good because of its goodness, not simply because God wills it.

        e. Given God’s creation of the universe and given its pre-established harmony everything that happens is determined to occur as it does by God.

11. Human BeingsAs rational souls, human beings exhibit a likeness to God; they are capable of morality and community with God—what Leibniz calls the City of God (an updating of St. Augustine—RY). Our souls also are immortal, although this does not seem to be true of animal souls.

12. Determinism and Free Will

        a. All human actions are determined; but they are not determined externally, because all our actions are developments (representations) of our own internal principle as monads. (Of course, what the internal principle is, is determined by God—RY.)

        b. Discourse on Metaphysics: "God determines [inclines] our will to choose what seems better, without however necessitating it" (text, p. 202). Given his distinction between necessary and contingent truths, Leibniz can say that what we will is a certainty, although it is not necessitated because there is no contradiction in our willing differently. (See section 13 in the Discourse—RY.) Accordingly we could have acted differently in a theoretical sense, if not in actuality.

        c. Leibniz points out that although we are determined, we as finite beings do not know what we are determined to do; so we must choose as best we can.

        d. How human beings act in a moral sense is affected by God’s grace; and not all human beings receive an equal amount of grace. We may not be able to understand why God does this, but God has appropriate reasons.

        e. Consolation: Since God has determined everything to occur as it does in the best of all possible worlds, we can be assured that any evil that occurs will be outweighed by the greater good it brings about in the overall progress of nature. Accordingly, we should want to happen exactly what does happen; and therein lies a way of our willing freely.

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Last updated 3/29/04

© Copyright 2004 by Ron Yezzi