CHAPTER 15 Christia Mercer The Platonism at the Core of Leibniz's Philosophy INTRODUCTION In 1714, Leibniz makes a striking pronouncement about the relation between the explicit claims of a philosopher and the underlying sources of those claims. He says that in order to understand the intellectual 'discoveries' of others, it is often necessary 'to detect the source of their invention'.1 Historians of philosophy have missed much about Leibniz's 'discoveries' because they have not identified the sources of his philosophical 'inventions'. In Leibniz's Metaphysics:its Origins and Development, I argue that in order to discern the subtle details of many of his views, we need to excavate their sources. To this end, I find it helpful to point to the humanist sources for what I call his metaphysics of method; to Aristotelian sources for his metaphysics of substance and to Platonist sources for his metaphysics of divinity. It was as a student in Leipzig that he learned about these three philosophical traditions. That is, the main professors in Leipzig-Johann Adam Scherzer and Jakob Thomasius-bequeathed to the young Leibniz a methodology of reconciliation and a thorough education in Aristotelianism and Platonism.2 Concerning Leibniz's metaphysics of method, suffice it to say that he attempted to combine major ideas from a variety of philosophical traditions. We find evidence of this 1 Gottfried Wilhelm Leibniz, Die Philosophischen Schriften, ed. C.I. Gerhardt, 7 vols (Berlin: Weidemann Buchhandlung, 1875-1890; reprinted Hildesheim: Georg Olms, 1978) (hereafter G, followed by the relevant volume and page numbers), III 568. 2 See my Leibniz's Metaphysics: Its Origins and Development (New York: Cambridge University Press, 2001), passim. D. Hedley and S. Hutton (eds.), Platonism at the Origins of Modernity: Studies on Platonism and Early Modern Philosophy, 225–238. © 2008 Springer. 225 226 Christia Mercer conciliatory eclecticism in some of major texts. Consider, for example, this comment made about his philosophical system in 1703–1705, for John Locke: This system appears to unite Plato with Democritus, Aristotle with Descartes, the scholastics with the moderns, theology and morality with reason. It seems to take the best from all quarters and then goes further than anyone has done before. ... I now see what Plato had in mind when he talked about matter as an imperfect and transitory being; what Aristotle meant by his 'entelechy'...; how far the sceptics were right in decrying the senses. ... Indeed, you will be surprised, Sir, at all I have to tell you, especially when you comprehend how much it elevates our knowledge of the greatness and perfection of God.3 Although Leibniz's metaphysics of method has not been previously noted, his metaphysics of substance is quite well known. We find one of the more famous summaries of it in Discourse on Metaphysics 8, where Leibniz writes: 'the nature of an individual substance is to have a notion so complete that it is sufficient to allow us to deduce from it all the predicates of the subject to which this notion is attributed'.4 Despite the attention given to this notion of substance, many questions have remained unanswered because historians of philosophy have not noticed that the 'source' of part of this 'invention' is thoroughly Platonist. For example, compare his claims about substance in Discourse on Metaphysics 8 to those in Discourse on Metaphysics 14: 'it is very evident that created substances depend upon God, who preserves them and who even produces them continually by a kind of emanation, just as we produce our thoughts. Indeed God . . . produces them . . . in order to manifest his glory'.5 It is surely not immediately obvious how a created substance is supposed to be both an emanation of God and something that has a complete concept. In order to grasp Leibniz's conception of the relation between God and created substance, that is, in order to understand his metaphysics of divinity, we need to discern the Platonism at the core of his philosophy. In order to discern that Platonism, we need to identify the Platonist doctrines which constitute the source of Leibniz's invention. SPECIFIC PLATONIST CONTEXT In a letter of 1706, Leibniz writes that: 'as a boy . . . Plato and with him Plotinus appealed to me'.6 The young Leibniz developed this appreciation for Plato and Plotinus with the help of his professors in Leipzig, especially 3 Gottfried Wilhelm Leibniz, Sämtliche Schriften und Briefe, ed. Deutsche Akademie der Wissenschaften, Berlin: Akademie Verlag, (1923–). References to this work hereinafter are abbreviated to 'A' followed by the series, volume and page numbers. This citation from the Nouveaux essais sur l'entendement is A VI vi 71–73. 4 A VI iv [B] 1540. 5 Ibid., 1550. 6 G III, 606. 15 The Platonism at the Core of Leibniz's Philosophy 227 Scherzer7 and Thomasius.8 Scherzer was generally well educated in Platonism and familiar with Kabbalism, but Thomasius was unusually erudite. He refers to the whole range of ancient, medieval and Renaissance Platonists and moves easily between pagan and Christian authors. There are four doctrines, which I take to be 'markers' of Platonism, which Scherzer and Thomasius both accepted, and which I would like to summarise as succinctly as possible now. Leibniz came to accept each of these doctrines and, as a group, they constitute the philosophical inspiration for a major part of his metaphysics. Before turning to these doctrines, however, it will be helpful to acknowledge the assumption that underlies all of them, namely, the view that God is in everything and everything is in God. On this point, the great Renaissance Platonist, Marsilio Ficino offers a particularly vivid account. In a dialogue between God and the soul, Ficino has God explain, 'I am both with you and within you. I am indeed with you, because I am in you; I am in you, because you are in me. If you were not in me you would not be in yourself, indeed, you would not be at all'. God continues: Behold, I say, do you not see? I fill heaven and earth, I penetrate and contain them. I fill and am not filled, for I am fullness itself. I penetrate and am not penetrated, for I am the power of penetration itself. I contain and am not contained, for I am containing itself. . . . Behold, do you not see? I pass into everything unmingled, so that I may surpass all; for I am excellence itself. I excel everything without being separate, so that I am also able to enter and permeate at the same time, to enter completely and to make one, being unity itself, through which all things are made and endure, and which all things seek.9 In brief, God exclaims: 'in me are all things, out of me come all things and by me are all things sustained forever and everywhere'.10 As Ficino's divine speech suggests, the Supreme Being is self-sufficient and exists independently of its creatures, the creatures depend fully and constantly on it. In this context, it is worth remembering that, for many Platonists, the Platonic Forms or Ideas were 7 Scherzer's works include: Trifolium Orientale, Leipzig: J. Bauer 1663; Collegii Anti-Sociniani, 3rd edn. (Leipzig and Frankfurt: N. Scipio, 1702); Vade Mecum sive Manuale Philosophicum Qvadripartitum (Leipzig, 1654). For more on Scherzer, see my Leibniz's Metaphysics, passim. 8 Thomasius' works include: Breviarium Ethicorum Aristotelis ad Nicomachum, Leipzig, 1658; Schediasma Historicum (Leipzig, 1665); Physica, perpetuo dialogo (Leipzig: G. H. Frommann, 1670; 1705); Physica; Logica; Metaphysica, and Rhetorica, published together, (Leipzig, 1692); Dissertationes LXIII & varii argumenti magnam partem ad historiam philosophicam & ecclesiasticam pertinentes (Halle, 1693); Origines historiae philosophicae & ecclesiasticae (Halle, 1699); Exercitatio de Stoica Mundi Exustione (Leipzig: F. Lanckisius, 1676). The latter is especially interesting concerning his Platonism. 9 Ficino, Dialogus inter Deum et animam theologicus, Letter to Michele Mercati, in Marsilio Ficino, Lettere, epistolarum familiarium liber I, ed. Sebastiano Gentile (Florence: Leo S. Olschki, 1990), I, 4, 30–50. 10 Ibid. 228 Christia Mercer taken to be Ideas in the mind of God which the divine mind was supposed to conceive and then use as models for the things of the world. With this said, let's turn to the first of our four Platonist doctrines. The Theory of Emanative Causation claims that, for a being A that is more perfect than a being B, A can emanate its attribute f-ness to B in such a way that neither A nor A's f-ness is depleted in any way, while B has f-ness, though in a manner inferior to the way it exists in A. The emanative process is continual so that B will instantiate f-ness if and only if A emanates f-ness to it. The Supreme Being is in the creatures in the sense that it emanates its attributes to them; it remains transcendent from them because it neither loses anything in the emanative process nor gives them any part of itself. The crucial point to understand is that the attributes exist in the products in a manner inferior to the way in which they exist in the Divine. God has the form or Idea f perfectly; creature has it imperfectly. This brings us to our second doctrine-what I shall call the Creaturely Inferiority Complex. This asserts that every product of the supreme being contains all the attributes which constitute the divine essence though the product instantiates each of those attributes in a manner inferior to the way in which they exist in the supreme being. It is relevant to our discussion that the diversity among creatures or the multiplicity in the world follows from the fact that creatures will instantiate the divine attributes in different ways and to different degrees. My justice is different from the justice of Socrates, and no doubt is inferior to his. Our first two claims offer an account of the relation between the transcendent God or Supreme Being and each of its creatures. Our third treats the relation between God and the whole of creation. Early Platonists like Plotinus and Philo of Alexandria are very clear on this point. According to Plotinus, for example, the One emanates unity to every individual creature, but it also emanates unity to the whole of creation. The result of this unity among the parts of the world was supposed to be a cosmic sympathy. Philo of Alexandria is particularly elegant on this point. He explains: And being superior to, and being also external to the world that he has made, he nevertheless fills the whole world with himself; for, having by his own power extended it to its utmost limits, he has connected every portion with another portion according to the principles of harmony.11 For someone who believes that every creature is a manifestation of the divine essence, it would reasonably follow that there exists an order connecting each instantiation to every other. Our third doctrine is a summary of this basic point. The Relation of Sympathy, which can be more or less, claims that each created being corresponds to the activity and states of all the beings. The fourth Platonist doctrine relevant here is epistemological and concerns how a human being might come to glimpse God. I have already noted that God 11 Philo, On the Posterity of Cain, in The Works of Philo, trans. C.D. Yonge (Peabody, MA: Hendrickson Publishers, 1993), V, 14. 15 The Platonism at the Core of Leibniz's Philosophy 229 is in the world in the sense that the divine Ideas or attributes are constantly emanated to creatures. But for many Platonists, these Ideas also exist in the human mind as potential objects of knowledge. Although philosophers differed about the precise role played by the senses in the acquisition of knowledge, most agreed that the process of coming to know the Ideas was one of removing oneself from the mutable world of the senses and discovering the immutable Ideas within. The acquisition of knowledge was considered an arduous, internal journey that required rigorous intellectual and moral discipline. The point of philosophy therefore was to raise oneself above the petty concerns of this world, to concentrate on the eternal truths, and eventually to acquire knowledge of the supreme being. As Ficino has God make the point in the dialogue with the soul, 'In order to take hold of me, do not be drawn in many directions. I am unity itself. Stop movement, unify diversity, and you will surely reach me, who long ago reached you'.12 Notice the importance that Ficino places on the unity of God as an aid in the pursuit of truth. Philo is particularly explicit on this point. He warns: do not... employ yourselves in the investigation of the earth ..., but rather seek to become acquainted with yourselves and your own nature, and do not prefer to dwell anywhere else, rather than in yourselves. For by contemplating the things which are to be seen in your own dwelling ... you will ... arrive at a correct knowledge of God and of his works. For you will perceive that there is a mind in you and in the universe.13 For our purposes, it is noteworthy that Philo takes there to be (at least) two necessary steps in the acquisition of wisdom: first, we must consider 'this invisible chain of harmony and unity, which connects all those parts' of the world; and then God must 'cause the light of truth to shine' so that our intellect can contemplate some of the Ideas.14 The goal of life therefore is to remove oneself as much as possible from the ties to the material world and to contemplate the eternal and immutable Ideas within. Because the mind is mutable and finite, it can never grasp the whole of its contents; with the help of God however it can grasp some part of it. The fourth doctrine here (which I term, Epistemological Assumption) claims (1) that the mind is the object of knowledge in the sense that it contains the eternal truths or Ideas; (2) that the mind, which is mutable and finite, will become aware of those objects only if it both turns away from the material world and is aided by the divine light; and (3) that it is the intellect or understanding that is capable of grasping those truths. Leibniz embraced all four of these Platonist doctrines. For example, in 1668–1669, just as the young man was developing the core features of his metaphysics, he offers his first general account of the relation between God and creatures, which 12 Ficino, Dialogus inter Deum et animam theologicus I, 4, 50–55. 13 Philo, On the Migration of Abraham, in The Works of Philo, trans. C.D. Yonge, XXXIII, 185–186. 14 Ibid., XIV. 76. 230 Christia Mercer he says is similar to 'Plato in the Timaeus about the world soul', to 'Aristotle in the Metaphysics and Physics about the agent Intellect', to the Stoics and others. Like these other philosophers, he maintains that God is 'diffused through everything'.15 As I argue elsewhere, some of Leibniz's most well known doctrines-for example, the principle of the identity of indiscernibles, the theory of expression, and the theory of pre-established harmony-grew out of his commitment to these four Platonist doctrines.16 In the remainder of this paper, I would like to go beyond my previously published work to offer a brief account of the Platonist epistemology at the core of Leibniz's thought. I discuss Leibniz's epistemology for two reasons. First, although scholars have long noted Leibniz's innatism, there has not been a systematic study of what he considers to be the proper journey to the truth, nor does my book include a complete account.17 Second, as far as I know, scholars have not given proper attention to the Platonist roots of Leibniz's epistemology. This oversight is striking, since Leibniz is explicit about his admiration for Platonism on topics concerning knowledge. For example, in Discourse on Metaphysics 26 and 27, he complains that Aristotle 'maintains that there is nothing in our soul that does not come from the senses'. Unlike Aristotle, he continues, Plato, 'goes deeper . . . Indeed, Plato taught that our soul expresses God, the universe, and all essences'.18 LEIBNIZ'S METAPHYSICS OF DIVINITY: PRE-ESTABLISHED HARMONY Since Leibniz's epistemology is best seen within the philosophical context of pre-established harmony, let me review the Platonist sources of this, Leibniz's most famous doctrine. Pre-established harmony is primarily an account of the interrelations among simple substances or monads, where the rough idea is that substances do not causally interact, but respond perfectly to the activities of each other. Each monad acts eternally according to its own complete concept, but it does so in a way that is perfectly parallel with every other substance. I wiggle my fingers; wiggling my fingers is part of what it is to be the individual I am. You see me wiggle my fingers because it is part of your complete concept to do so and because your individual concept and mine are perfectly parallel. 15 A VI i 511. For further textual evidence that Leibniz accepts the four Platonist doctrines, see my Leibniz's Metaphysics, chs. 6–8. 16 For the full account of all these doctrines, see my Leibniz's Metaphysics, esp. chs. 6, 10. 17 A recent introduction to Leibniz's philosophy offers a concise and helpful account of his innatism. See Nicholas Jolley, Leibniz (London: Routledge, 2005), pp. 103–118. Notice however that Jolley, like so many scholars before him, does not offer a thorough-going account of Leibniz's epistemology. Independently of my work, Maria Rosa Antognazza has developed an equally broad approach to Leibniz's methodology. Her forthcoming biography of Leibniz promises to be of major importance. See Antognazza , Leibniz: An Intellectual Biography (Cambridge: Cambridge University Press, forthcoming). I am familiar with Antognazza's approach to Leibniz's thought based on recent conversations with her. 18 A VI iv [B] 1570–71. 15 The Platonism at the Core of Leibniz's Philosophy 231 I have shown elsewhere how pre-established harmony grew out of Leibniz's interpretation of the first three Platonist doctrines discussed above. In particular, the theory of pre-established harmony can be seen as a brilliant blending of sympathy and emanative harmony. For Leibniz, the relation between God and the world is emanative in the sense that God emanates the divine essence to every creature. The Creaturely Inferiority Complex requires that each substance be inferior to God and that substances will differ in the clarity of their expression or representation. We begin to see what Leibniz means when he describes the world as unity in diversity, unity in multiplicity. The world contains multiplicity because creatures express the divine essence in different ways. It is my view that Leibniz's famous principle of the identity of indiscernibles (roughly, that despite appearances to the contrary, there are no two substances exactly alike) grew out of his desire to fill the world with as many distinct versions of the divine essence as possible. The world contains unity because the Supreme Being emanates its unity to each individual creature, and to the totality of creatures. The parallelism of pre-established harmony is merely an extension of the Platonist notion of sympathy: each substance, in its manifestation of the divine essence, is in perfect sympathy-for Leibniz, in perfect coordination-with every other. Pre-established harmony just is emanation and sympathy perfectly organised.19 LEIBNIZ'S METAPHYSICS OF DIVINITY: DIVINE KNOWLEDGE For anyone who accepts the Theory of Emanative Causation and the view that the Supreme Being emanates the divine nature to everything in the world, it would seem to be fairly easy to grasp God in the world. Plotinus nicely captures the underlying epistemological optimism of this conception of the world: For knowledge is a whole, and its parts are such that the whole remains and the parts derive from it. And the seed is a whole and the parts into which it naturally divides derive from it, and each part is a whole and the whole remains an undiminished whole. ... There [in the whole body of knowledge] all the parts are in a way actual at once; so each one which you wish to bring forward for use is ready; but in the part only that which is ready for use is actual; but it is given power by a kind of approach to the whole.20 Plotinus goes on to say that, every part of knowledge 'contains also all the other parts potentially' and therefore 'the knower in knowing [one part] brings in all the others by a kind of sequence'.21 19 For a fuller discussion and for citations to a range of works of Leibniz, see Leibniz's Metaphysics, esp. chs. 6, 8, 10. 20 Plotinus, Enneads, ed. and trans. A.H. Armstrong (Cambridge, MA: Harvard University Press, 1990) IV.9.5. 21 Ibid. 232 Christia Mercer Despite the epistemological benefits of the Theory of Emanative Causation, things are not quite as easy as they first appear. As the Epistemological Assumption suggests, the journey to the truth is an arduous one. The Hebrew and New Testaments often pose an obvious question, namely, how are human beings, who are so obviously finite and frail, supposed to grasp the infinite and supreme Creator? In Romans, Paul is perfectly clear about the problem. On the one hand, he writes, the seekers of truth 'are without excuse' in that what can be known about God has shown it [the truth] to them. Ever since the creation of the world his invisible nature, namely, his eternal power and deity, has been clearly perceived in the things that have been made.22 On the other hand, admits Paul, they 'became futile in their thinking and their senseless minds were darkened' so that 'claiming to be wise, they became fools' (Romans 1.18–23). For many theists, despite divine immanence, God is beyond the grasp of human beings. As long as the human understanding is trapped in its earthly, corporeal prison, how can it possibly progress from its finitude and frailty to infinity and perfection? There are two questions that have not been fully addressed concerning Leibniz's Platonist epistemology: what can we expect (at best) at the end of our earthly epistemological journey to God, and what is the means to that end? Given Leibniz's notorious optimism about the rationality and goodness of the world, we would expect his answers to be optimistic. They are not, and that in itself is interesting. Let's treat each of these questions in turn. DIVINE KNOWLEDGE: THE END OF THE JOURNEY Throughout his long philosophical career, Leibniz shows an interest in the possibility of a beatific vision. In 1668, he began work on a large project entitled Catholic Demonstrations, which was to include a discussion of a long list of theological and philosophical topics. It is clear from the outline of the project, which he composed in 1668–1669, that he intended to discuss the beatific vision. In his Conspectus he writes: [T]he beatific vision or [seu] the intuition of God, face to face, is the contemplation of the universal Harmony of things because GOD or [seu] the Mind of the Universe is nothing other than the harmony of things, or [seu] the principle of beauty in them.23 According to Leibniz, the goal of human life is the recognition of harmony where that is the same thing as the intuition of God: when we 'contemplate the universal Harmony of things', we are face to face with the Divine. That is, 22 A VI i 499. 23 Ibid. 15 The Platonism at the Core of Leibniz's Philosophy 233 Leibniz agrees with his Platonist predecessors that God is the single emanative source of all things and that the ascent to God is the recognition of this 'Mind' in the world.24 Two closely related questions arise from this analysis: precisely what sort of knowledge does the vision afford, and who exactly has it? That is, we need to know more about what sort of epistemological state this is and how to achieve it. In some notes on natural law written in 1670–1671, Leibniz develops for the first time his views about harmony and he is perfectly clear that the discernment of this worldly harmony requires that we grasp 'the infinity' of God. In one of these notes (of 1671), he writes for example: '[N]o one is able to have real knowledge of a single thing, unless he is most wise, that is [seu], has real universal knowledge'.25 What Leibniz suggests here and elsewhere is that to have any real knowledge of a thing just is to have knowledge of all the divine attributes. Since to have knowledge of all the divine attributes is to have knowledge of everything, it is not far-fetched to claim that to have real knowledge of one thing is equivalent to having universal knowledge. On this account of knowledge, infinite knowledge would seem to be a necessary condition for real knowledge; given the finitude of the human mind, it would seem to follow that human beings can have no 'real knowledge' of God. The textual evidence for this radical epistemological conclusion comes from early texts. Is there reason to believe that Leibniz maintains this stance? Consider an essay entitled Von der wahren Theologia mystica, written in German, probably in the final years of the seventeenth century. In the first part of the essay, Leibniz summarises the emanative relation between God and creatures, and then acknowledges the epistemological difficulties that follow. He writes: Every perfection flows immediately from God. Only the inner light that God himself kindles in us has the power to give us a right knowledge of God. The divine perfections are concealed in all things, but very few know how to discover them there. Hence there are many who are learned without being illumined, because they believe not God or the light but only their earthly teachers or their external senses and so remain in the contemplation of imperfections.26 We find here the same tension discovered in the early texts. On the one hand, the divine attributes or perfections are in everything in the world, waiting to be 'discovered'. On the other, they are very difficult to glimpse. In order to find these concealed objects of knowledge, we must escape the world of imperfections and contemplate God. But how? In Von der wahren Theologia mystica, Leibniz makes it clear that the key to his epistemology lies in his metaphysics. Although each created thing or 'self-being' is 'of God [Selbswesen von Gott], ... [e]very single self-sufficient thing 24 Ibid. 25 Ibid., 484. 26 Ibid. 234 Christia Mercer [Selbststand], such as I or you, is a unified, indivisible, indestructible thing'.27 That is, each creature acquires its being from God and yet exists as a separate unified thing. Moreover, Leibniz is clear about the fact that creatures differ from one another in the clarity of their expression of the divine essence: 'In each and every creature is everything, but with a certain degree of clarity [Kraft der Klarheit]'. In our separateness from God, it becomes difficult to recognise the divinity; in our connectedness to God, it becomes easy. Leibniz summarises the point: 'God is the easiest and the hardest being to know'.28 In Von der wahren Theologia mystica, Leibniz offers clues both about how to attain this easy knowledge and about how to move from that sort to the 'hardest' thing to know. The means to 'the essential truth' or the divinity in creatures is ourselves. In order to glimpse God we must turn to our 'spirit' or soul and find God there as the 'origin' of our substance or 'self-being' (Selbstwesen). The first significant step in this epistemological process is to acquire knowledge of some of the attributes of God: 'the knowledge of God is the beginning of wisdom, the divine attributes are the primary truths for the right order of knowledge'.29 Apparently, knowledge of the divine attributes is the 'easy' knowledge. But Leibniz also insists that this is just the first step to real knowledge. Ultimately, what we seek is 'the essential light' which is: the eternal Word of God, in which is all wisdom, all light, indeed the original of all beings and the origin of truths. Without the radiation of this light no ones achieves true faith, and without true faith no one attains blessedness.30 Leibniz dramatically summarises the convergence of his metaphysics and divine epistemology: in each mind, 'there lies an infinity, a footprint or reflection of the omniscience and omnipresence of God'. Were we to acquire this 'right knowledge of God', we would thereby attain 'all wisdom, all light, indeed the original of all beings and the origin of all truth'.31 We find the epistemological point of Von der wahren Theologia mystica essentially in agreement with the earlier texts: because God is contained in every created thing, to have real knowledge of anything is to know everything. It seems clear that human beings in their earthly existence will not attain true knowledge, wisdom, or the beatific vision. In the Philosopher's Confession of 1672–1673, we find evidence of this epistemological conservatism. Only after death, is 'the nearly perfect person' capable of conceiving God in the right way. With this cognition, there is 'an instantaneous metamorphosis' so that 'in a blink of the eye' beatitude occurs.32 27 Leibniz, Deutsche Schriften, ed. G.E. Guhrauer, 2 vols (Berlin: 1838–40), I, 410–411. 28 Ibid. 29 Ibid. 30 Ibid. 31 Ibid. 32 A VI iii 135. 15 The Platonism at the Core of Leibniz's Philosophy 235 Our epistemological prognosis does not look good. Although prior to death we seem to be able to acquire knowledge of some divine attributes, real knowledge seems to be beyond us. Because finite and frail human beings are incapable of acquiring infinite knowledge, it would seem to follow that they cannot achieve knowledge of God. Is there no way out of this trap? DIVINE KNOWLEDGE: THE JOURNEY ITSELF Yes and no. Despite Leibniz's well-known optimism about the goodness of the actual world, he was much more pessimistic than one might predict about the possibility of any thorough-going knowledge of the world's divine source. He was inclined to think that human frailty was genuine and that it is therefore impossible to have 'real knowledge'. But he was also prepared to offer some reason for hope. In the Philosopher's Confession of 1672–1673, he makes a distinction that diminishes the severity of our trap: Even an accurate cognition [exacta cognitio] can increase, not by novelty of matter, but by novelty of reflection. If you have nine units accessible to you, then you have comprehended accurately the essence of the number nine. However, even if you were to have the material for all its properties, nevertheless you would not have its form or reflection [formam seu reflexionem]. For even if you do not observe that three times three . . . and a thousand other combinations are nine, you have nonetheless thought of the essence of the number nine. . . . I will give an example of a finite thing representing [praebentis] properties that are infinite without any comparison with external things. Here is a circle: if you know that all the lines from the center to the circumference are equal, in my opinion, you consider its essence sufficiently clearly. Still you have not comprehended in virtue of that innumerable theorems.33 We have here a distinction between the cognition of the essence of something and its complete cognition. The former consists of the ('exact') understanding of an essential property; the latter involves the cognition of all its properties. In an essay of December, 1675, Leibniz uses different terminology to describe the same distinction: we do not have any idea of a circle, such as there is in God, who thinks all things at the same time. . . . We think about a circle, we provide demonstrations about a circle, we recognize a circle: its essence is known to us - but only part by part. If we were to think of the whole essence of a circle at the same time, then we would have the idea of a circle.34 Leibniz's point may be put as follows: to have complete knowledge of an essence E is to know all its properties. Since, according to Leibniz, every essence of 33 Ibid., pp. 139–140. 34 Ibid., p. 463. 236 Christia Mercer the relevant sort has an infinity of properties, only God can have this sort of knowledge. But finite human beings are capable of having some knowledge of E: when we grasp some property of E, we thereby have knowledge of E, though only partial. By piecing together these and other clues, we attain the following: for any essence E, whether infinite or finite, there is a range of possible cognitions of it, from partial to complete, where a partial cognition of E is to grasp one of its properties and a complete cognition of E is to grasp every such property. Moreover, for any essence E, whether infinite or finite, it may be 'represented' or 'expressed' more or less clearly, although each property of E is a partial expression of it. The bad news is that no finite human being will be able to have a complete cognition of any infinite essence and therefore of any divine attribute. A passage from the De Summa Rerum papers offers some help. In April 1676, Leibniz explains: 'Just as the number 3 is one thing, and 1, 1, 1 is another, for 3 is 1 + 1 + 1. To this extent the form of the number 3 is different from all its parts; in the same way [created] things differ from God, who is all things'.35 For any essence, say, 6, there is an infinity of expressions of it. For any one of these, say, 3 + 3, to grasp it is to grasp the essence of 6. By analogy, if I have a partial understanding of any property or attribute of God, then I have understood the essence of God. But not the whole essence. Whether I have a partial understanding of 3 + 3, or a partial understanding of justice, I have only remotely glimpsed the infinite complexity and glory of the divine nature. I have nonetheless glimpsed the divinity. The arithmetical analogy (which Leibniz uses throughout the De summa rerum papers) allows us to see how, despite our finitude and frailty, we are capable of grasping God. If I come to understand a property of justice, then I have a partial cognition of the essence of justice. Since justice is a divine attribute, it follows that I also have a partial cognition of God. Although there is a huge epistemological divide between a partial and complete understanding of justice, and an even greater one between a partial understanding of justice and a complete understanding of God, it is nonetheless true that to understand any Idea partially is to have a partial understanding of God and hence be on the path to a more complete knowledge. So, just as to understand a circle fully is to grasp every possible property or expression of its essence, to understand the Supreme Being fully is to grasp every attribute of it. It is a relief to discover that all knowledge is knowledge of God. But the meagerness of this partial knowledge leaves us pitifully remote from the beatific vision and the 'real' knowledge accompanying that vision. According to Leibniz, however, we should not despair about the finitude of our epistemological stance. There are at least two reasons for this. First, like Plotinus, Leibniz is committed to the underlying interconnectedness of knowledge so that to know one thing is potentially to know everything. Thus, to know the most meager properties of the divine essence places us squarely on the road to more complete knowledge. 35 Ibid., p. 512. 15 The Platonism at the Core of Leibniz's Philosophy 237 Second, Leibniz suggests that slow but steady (epistemological) steps are morally appropriate. He writes in an essay probably of 1675: 'It is a great boon to the human race that infinite things resist' our finite understandings. Because of our limited understandings, we cannot so easily 'crawl straight into the middle of the brambles' where we would become lost. Rather, our finite understanding forces us to struggle morally in the appropriate way. The suggestion is that the development of happiness and the increase of knowledge are closely related, and that we need to learn to be happy in the right manner before we are prepared to acquire more knowledge. It is therefore a good thing that 'the human race progresses towards improvement only gradually'. Moreover, despite our finite understanding and meager knowledge, 'a certain happiness is already in our power', and it is this happiness that deserves careful augmentation.36 In a related essay of 1676, entitled On the Happy Life, Leibniz offers us an account of a happy or tranquil life. To be tranquil, explains Leibniz, we must carefully follow 'the dictates of reason', assiduously avoid being led astray by 'passions and appetites', and content ourselves with the goods that we possess. In short, we will attain 'tranquility of the Soul' when we accustom ourselves to our lot in life and reflect on what we know.37 Tranquility and reflection will encourage greater happiness and more complete knowledge. In another text of 1678–1679, Leibniz suggests that this relation between knowledge and happiness is the lesson of Plato's Phaedo: that is, through the pursuit of divine knowledge 'lofty souls' will attain true happiness in the afterlife.38 CONCLUSION Given Leibniz's conciliatory methodology and his goal of combining the truths of Platonism with those of Aristotle, the core of his philosophy has not been the easiest to know. But once we put his texts in their proper Platonist context, we are able to discern the Platonism at the core of his philosophy and recognise the profoundly original use to which he put those rich and subtle traditions. That is, as Leibniz recommends in the letter with which I began this paper, by 'detecting' the 'source' of his 'inventions', we have been able to recognise the Platonism at its core. We have found that, at the very center of Leibniz's philosophy, is the Platonist theory of emanation. Like Philo, Plotinus and many other Platonists, he takes the world to be a likeness of God. Like Plotinus, he believes that each 'part' of knowledge 'contains also all the other parts potentially'. For Leibniz, in order to glimpse God, all we have to do is escape 'the shadow world' and have a 36 Ibid., pp. 428–429. Some of this material is contained in my 'Leibniz on Knowledge and God', American Catholic Philosophical Quarterly, 76(4), 531–550. 37 A VI iii 636. 38 See Sentiments De Socrate, A VI iv [B] 1386–1388. 238 Christia Mercer momentary insight in any area of knowledge. When we consider 'the footprint' of God in our minds and manage to grasp a property of an attribute of God, we have thereby grasped some part of God's essence. All such knowledge is knowledge of God; each part of this knowledge is a first step toward universal knowledge and the beatific vision. It is this sense that 'God is the easiest and the hardest being to know'.