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Idea and Ontology

An Essay in Early Modern Metaphysics of Ideas

Marc A. Hight


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Idea and Ontology

An Essay in Early Modern Metaphysics of Ideas

Marc A. Hight

“Marc Hight’s book deals in great depth with the ontology of ideas in the early modern period, concentrating principally on Descartes, Malebranche, Leibniz, Locke, Berkeley, and Hume. He shows that there is a great deal still to be learned on this traditional topic as it concerns each of these great philosophers. Hight’s insightful and very well-defended interpretations will likely excite important new interest and debate on this central topic.”


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The prevailing view about the history of early modern philosophy, which the author dubs “the early modern tale” and wants to convince us is really a fairy tale, has it that the focus on ideas as a solution to various epistemological puzzles, first introduced by Descartes, created difficulties for the traditional ontological scheme of substance and mode. The early modern tale depicts the development of “the way of ideas” as abandoning ontology at least by the time of Berkeley. This, in turn, fostered an antimetaphysical bias as modern philosophy developed further, elevating epistemology to its current primary status in the field.

Marc Hight challenges this account by showing how, though the conception of ideas changed over time, the ontological status of ideas remained a central part of the discussion about ideas and influenced how even later thinkers like Locke, Berkeley, and Hume thought about them. By his reading of important texts in early modern philosophy, Hight aims not only to provide a more accurate history of philosophy for this period but also to resuscitate the value of metaphysics for philosophical analysis today.

“Marc Hight’s book deals in great depth with the ontology of ideas in the early modern period, concentrating principally on Descartes, Malebranche, Leibniz, Locke, Berkeley, and Hume. He shows that there is a great deal still to be learned on this traditional topic as it concerns each of these great philosophers. Hight’s insightful and very well-defended interpretations will likely excite important new interest and debate on this central topic.”
“A wide-ranging study of the ‘way of ideas’ and its metaphysics, culminating in a bold reinterpretation of Berkeley.”
Idea and Ontology is an important book that should change our thinking about the development of philosophy in the pre-Kantian period. With care, attention to detail, and philosophical rigor, Hight systematically demolishes the popular ‘early modern tale’ about an epistemological turn and shows the ineliminability of the question ‘What kind of thing is an idea?’ Hight’s sympathetic and sophisticated interpretation of Berkeley is rightly placed center stage in his account of the progress from Descartes to Hume and gives us a new insight into his relation to his predecessors and especially to Locke. While Locke shied away from ontological questions in favor of the epistemological, Hight’s Berkeley sees the importance of taking ontology as seriously as epistemology if he is to save the ordinary commitment to naïve realism from the skeptical threat posed by the theory of ideas.”
“Hight’s book is a very interesting and original inquiry into the difficulty early modern philosophers had in reconciling the central concept of ‘idea’ with traditional ontological categories like substance and mode. Hight’s point is that the claim of some early moderns to avoid those categories has significant difficulties, since the notion of ‘idea’ in some ways has the properties of a mode and in other ways the properties of a substance.”
“Well written and clearly argued.”

Marc A. Hight is Elliott Associate Professor of Philosophy at Hampden-Sydney College.



List of Abbreviations

Introduction: Idea Ontology and the Early Modern Tale

1. The Traditional Ontology

1.1 Substance

1.2 Modes

1.3 What Is an Idea?

1.4 Stretching Idea Ontologies

2. Descartes

2.1 Representation

2.2 Perception, Ideas, and Images

2.3 Innate Ideas, Dispositions, and Causes

2.4 The Complications of the Passions

3. The Cartesians: Malebranche and Arnauld

3.1 Malebranche’s Theory of Ideas

3.2 Substantializing Ideas

3.3 Attacking Modes

3.4 A New Ontology?

3.5 Arnauld’s Theory of Ideas

3.6 Critique of Malebranche

3.7 The Cartesian Debate

4. Locke

4.1 Locke “Deontologized”

4.2 Lennon’s Locke

4.3 Locke’s Contemporaries

4.4 Locke’s Implicit Ontology

5. Leibniz

5.1 Resolving a “Tension”

5.2 Ideas as Dispositions

5.3 Reading Leibniz

5.4 Ideas: Being One vs. Having One

5.5 Innate Ideas

5.6 Difficulties with Dispositions

5.7 Ideas as Modes

6. Berkeley

6.1 Minds and Ideas

6.2 Ideas as Objects

6.3 Ideas as Modes

6.4 Qualities

6.5 Unperceived Existence

6.6 Phenomenalism

6.7 Berkeley and the Early Modern Tale

7. Divine Ideas

7.1 Divine Ideas and Archetypes

7.2 “In” the Mind of God

7.3 Permutations

7.4 Defending Berkeley’s Theory of Divine Ideas

7.5 Fleeting Ideas

8. Abstraction and Heterogeneity

8.1 Abstract Ideas

8.2 Kinds of Abstraction

8.3 Berkeley’s Attack

8.4 Berkeley’s Solution: General Ideas

8.5 Perceptual Heterogeneity

8.6 The Molyneux Thought Experiment

8.7 The Argument from Difference in Content

8.8 Adding Visible and Tangible Lines

8.9 Heterogeneity and the Nature of Ideas

8.10 Ontology to Heterogeneity

9. Hume and Idea Ontology

9.1 Perceptions as Substances

9.2 Dependent Perceptions

9.3 Concluding Remarks: The Demise of the Early Modern Tale




Idea Ontology and the Early Modern Tale

Traditional metaphysics has not fared well since its glory days in the early modern period. Gone is the fascination with developing an ontology that can account for our experiences in the world. Cartesian dualism, Leibnizian monads, Berkeleian immaterialism, and similar metaphysical investigations have been replaced by discussions of language, confident assertions that epistemology alone is first philosophy, and pronouncements that ontology is dead. Hilary Putnam has even delivered a talk in a distinguished lecture series entitled “Ontology: An Obituary” (2004, 71–88). It is not that metaphysics is no longer studied or held in historical esteem; rather the guiding assumption today seems to be that we have advanced far enough to recognize that ontology is an exhausted—perhaps useless—enterprise. It seems we have nothing left to learn from ontological speculation and metaphysical system building.

Whence this antimetaphysical attitude? John Heil argues that an implicit adherence to a Wittgensteinian picture theory is to blame, but I suspect the roots are spread more broadly and deeply. The dominant view is that ontology has relatively little to offer contemporary philosophers. The early moderns generally had robust, rich ontologies, but this robustness became an embarrassment when it was discovered that no ontology appeared to fit well with the powerful new theory of ideas. Here we find a historical pedigree for contemporary antimetaphysical views. If one wants to undercut the importance of metaphysics and ontology, then pointing to historical developments that support this attitude can be a potent tool. This is, in fact, precisely what has been happening. Early modern scholarship (often unconsciously influenced by contemporary thinking) had, so the argument goes, developed strains of thought bent on establishing the primacy of epistemology by the time philosophers like Berkeley became active. Thus one lesson that history is supposed to teach us is that, between the time of Descartes and Berkeley, the early moderns learned that ontology could not provide the answers we seek about the world. The point is made by targeting the concept most vital to all of these discussions: that of an idea. If the early moderns abandoned ontology with respect to ideas (so that we need not ask ontological questions about them because they are idle or do not apply), then today we are on firmer ground setting aside metaphysics and ontology generally. A story has thus been developed and told so often that it is now routinely thought of as the traditional view of what transpired in the early modern period. I call this the early modern tale.

The tale told about seventeenth- and eighteenth-century philosophy runs roughly as follows. Descartes broke free of the fetters of Scholasticism by simultaneously advancing a new mechanistic theory of the physical world and a new concept of the mental that relegated many of the features of ordinary experience to the mind. To facilitate the latter move, he reached up and brought ideas down from the heavens—historically, ideas had been understood to be purely divine entities—and applied them to finite creatures in the mundane world. Ideas thus spread in meaning to cover thoughts, images, concepts, and sensations. Ideas played the crucial role in early modern epistemology; to discover how they functioned and represented the world was to discover the mechanism by which everything could be known. The new way of ideas promised scientific access to a universe the old Aristotelian system could not imagine, much less explain. But alas, as the story goes, the new system did not work. The way of ideas was a poor fit with the traditional ontological categories of substance and mode. Descartes and his earliest followers did not completely grasp this fact. There were good reasons both for denying that ideas could be modes of the mind and for denying that ideas could be substances. In light of this, subsequent thinkers, though following Descartes’ lead, slowly eroded the Cartesian metaphysical framework. The promise of idea philosophy was too strong to be fettered by ontological chains. At its core, Descartes’ philosophy still adhered to the traditional substance/property ontology of its predecessors. Thus when the Cartesian system began to break down, its ontology did as well. Yet perhaps its most crucial element, its theory of ideas, flourished, and it dominated the philosophical scene long after the heyday of Cartesianism.

Why did idea philosophy flourish when its ontology was allegedly faltering? Our early modern tale tells us that advances in the philosophy of ideas led the moderns not only to reject the old ontology but also to abandon ontology altogether with respect to ideas. This is not to say that ontology in general was abandoned. Yet ideas in particular were not deemed susceptible to ontic analysis because they had no ontological status at all. Thus scholars like Richard Watson and John Yolton argue that the main figures of the early modern period undermined the exclusive and exhaustive nature of substance and mode. Here is one representative example of the tale in action, as told by Yolton:

The point of this last remark [made by Locke in reply to Norris] is that Locke did not consider ideas to have an ontological status; he wanted to concentrate upon their role in perception and knowledge. Having Malebranche’s theory as an example of a theory that gave to ideas an ontological status, Locke had a twofold reaction: he rejected Norris’s attempts to fit ideas into the standard ontological categories of substance or mode, and he stressed the cognitive, awareness features of ideas. The language of “having ideas” is identified with being aware, with perceiving. (1984, 94, emphasis in the original)

What it means to deny that ideas have an ontological status is a matter open for discussion and analysis. What matters for the present is that this tale is being told at all. Locke allegedly starts the assault on substance by attacking our conception of it. Perhaps the problem with characterizing the nature of ideas lies with the very notions we have about ontological categories. Substance is, in Locke’s famous phrase, an “I know not what.” Locke is not merely setting aside a discussion of ontology in the Essay Concerning Human Understanding; according to the early modern tale, when it comes to ideas, he is abandoning it. Most scholars, of course, do not jump immediately to this radical conclusion. But its basic thrust pervades a lot of the work done on the early moderns. If Locke does not abandon ontology for ideas, he is at least pointing us in that direction. Thus D. J. O’Connor writes: “In Berkeley’s words, he [Locke] ‘bantered [i.e., challenged] the idea of substance’ and though he himself did no more than point the way to his successors, the traditional theory never recovered from the attack which he led” (1967, 73). O’Connor himself does not take the step of alleging that Locke abandoned ontology with respect to ideas. Yet even in accounts that deal squarely with the ontologies of various early modern philosophers, there is an undercurrent that pushes one to think either that the ontology is of historical interest only or that it is being scrutinized solely for the purposes of revising its emphases to give it more contemporary relevance. This undercurrent may be felt more keenly with respect to the nature of ideas. Thus even where the presence of the early modern tale is not explicit, its influence often lurks nearby.

The famous immaterialist George Berkeley is the key to the early modern tale. He denies that we can have any reasonable conception of material substance and his own ontology of ideas allegedly reveals either that the way of ideas reduces to epistemology alone or that the modern penchant for ontology is sadly, if imaginatively, misguided. Some ascribe roles to other philosophers (most notably Hume), but once Berkeley is folded into the tale the story is essentially complete. Hume’s primary contribution in this context is that he continues the story already implicit in Berkeley’s system. To use Yolton’s expression, ideas in the early modern period are “deontologized” by the time we reach Berkeley.

The problem, however, is that the early modern tale is actually a fairy tale. The early moderns did not abandon ontology when it came to their reasoning about the nature of ideas. They preserved an idea ontology. Asserting that there must be an ontology of ideas does not imply, however, that there were no tensions between the way of ideas and the traditional substance/mode ontology. The friction between the epistemological roles of ideas and their ontic status is one of the key elements driving developments in metaphysics in the modern period. A core traditional ontology was never abandoned but instead occasionally “stretched” owing to the new pressures that the introduction of ideas brought to bear on it. This work aims to establish that the early moderns remained committed to a more or less traditional ontology with respect to ideas and that reading the early moderns as idea ontologists results in better philosophy and more accurate history.

What, then, was the early modern conception of ideas that our key figures—philosophers such as Descartes, Arnauld, Malebranche, Locke, Leibniz, Berkeley, and Hume—inherited, and how did it contribute to the destabilization of the substance/property (mode) ontology without leading to its abandonment? What were the effects of this interplay between ideas and the traditional ontology? These questions frame this project and lead to its conclusion. I discuss this “breakdown,” first by exploring the nature of the traditional ontology and then by examining how select philosophers, emphasizing Berkeley, struggled to place ideas within it. In the end, I conclude that the moderns did not abandon the substance/mode ontology for ideas. The radicalization of early modern metaphysical systems (the adoption of more unusual metaphysical positions, like immaterialism and Humean skepticism) is attributable primarily to the poor fit between the epistemological roles played by ideas and the substance/mode ontology. This radicalization, however, is evidence of how the moderns sought to retain the traditional ontological categories, even if their attempts were not always successful. Hume’s work demonstrates the point, since he embraced much of Berkeley’s thinking about the nature of ideas but could not avail himself of Berkeley’s unusual solution. The moral is clear: insofar as one wants to understand early modern thinking, especially about ideas, one needs to use the traditional ontological distinctions as a framework. The lesson is especially true for Berkeley, who will correspondingly take center stage in this study; it is also true, to a lesser extent, for Hume, with whom this study will conclude.

In order for this endeavor to make sense, we first need to explore the basic concepts and categories I employ. I start with an analysis of substance and mode as used by the moderns. Created substances (God is a special case) have to satisfy two key requirements: endurance and independence. Any entity that endures and underlies change without requiring any other kind of thing to exist is itself a substance. Modes are dependent modifications of substances. The analysis in the first chapter is important not only because it frames the discussion of subsequent chapters but also because it helps identify clues that will reveal whether a given philosopher treats ideas as substances or as modes. The issue is not always clear. Many historians of philosophy have sought to replace the language of substance and mode with talk about reification. Although the concept of reification is perhaps useful for some contemporary discussions, I argue that it is not when one is seeking to determine the ontological commitments of early modern philosophers.

The main part of the book offers a careful discussion of a select history of the ontology of ideas in the early modern period. This select history in turn is divided into two large sections. The first, mainly exegetical, part engages the perceptual theories and theories of ideas of Descartes and the early Cartesians. They are foundational figures in the development of the ontology of ideas and are not generally alleged to have abandoned ontology with respect to them; instead, they did important work in this area, work with which later philosophers were familiar. The inconclusive confrontation between Malebranche and Arnauld over the ontology of ideas led Locke and even contemporary commentators today to take the unusual step of sidestepping questions about ontology with respect to ideas. My task in these chapters is only to be clear about what these theories of ideas were and what sorts of problems confronted them; the aim is to provide a context for our more pressing analyses of later theories of ideas. Therefore it is not my intention to give a systematic history of the philosophy of ideas but only a history relevant to the development of the ontology of ideas.

Our first important early modern figure is of course Descartes, whose philosophy of ideas I engage in the second chapter. Descartes is important not only because he introduces the concept of idea that most of the moderns will essentially adopt but also because he has a rather difficult time fitting this concept of idea into his ontology. Descartes initially flirts with views that make ideas rather like corporeal substances. The problems with this early position are sufficiently obvious that he later adopts the familiar theory that makes ideas modes of the mind. Ultimately he endorses the interesting position that all ideas must be innate to the mind. The tangle of problems he leaves is inherited by the first generation of Cartesians, especially Malebranche and Arnauld, whose views I examine in the third chapter. The famous dispute between Malebranche and Arnauld over the status of ideas is all the more intriguing because both of them otherwise claim to be good Cartesians. The nature and quality of their arguments occupy my attention for most of the chapter, although I am forced to conclude that neither achieves a clear victory in their dispute.

The discussion through Arnauld sets the stage for the second part of the historical investigation, where I really begin to make my case for an ontological reading of the early moderns. Starting with the fourth chapter, which concerns Locke, I argue that key early modern figures remained committed to a traditional substance/mode ontology with respect to ideas. To this end, I employ both textual and philosophical arguments, since I also hold that, ceteris paribus, readings that make the early moderns both historically plausible and philosophically stronger are to be preferred.

Locke is our first central figure in the early modern tale, for it is with him that many advocates of the early modern tale believe that we can see the start of the “abandonment” of ontology with respect to ideas. In particular, I engage such scholars as Thomas Lennon and John Yolton, who argue that Locke has an exclusively epistemological understanding of ideas. In the fourth chapter I argue that although Locke did want to set aside certain questions of ontology, he nonetheless had an underlying implicit ontology of ideas. There are formidable textual and philosophical reasons for thinking that Locke reasoned within the confines of a substance/mode ontology even as he consciously preferred to explore issues more connected with epistemology than ontology. My analysis places considerable emphasis on the much-neglected “An Examination of P. Malebranche’s Opinion of Seeing All Things in God,” where Locke engages Malebranche and John Norris. I conclude that Locke does not abandon ontology with respect to ideas and thus cannot play the role allotted to him in the early modern tale.

I have elected not to include a chapter on Spinoza, primarily because he is not considered a vital figure in our fairy tale. Spinoza’s striking metaphysics dominates the rest of his philosophy and leaves little doubt that ideas—whatever their roles—are ultimately grounded in the ontology of substance and mode. In Ethics 2D3 Spinoza tells us, “By idea I understand a concept of the Mind that the Mind forms because it is a thinking thing.” In the explanation he goes on to point out that all ideas involve mental activity (which is why he says “concept” instead of “perception”). Spinoza also distinguishes the idea from its object (ideatum), preserving the Cartesian distinction between objective and formal reality. Ideas are a particular kind of mode of the one substance, God. The distinction between an idea and its object (and other uses to which Spinoza puts the term “object”) makes the analysis cloudy and difficult, but for my purposes here the core claim is not controversial: Spinoza does not contribute to the early modern tale nor am I aware of anyone who has attempted to make a case for his inclusion in it (CWS 1:447).

Like Spinoza, Leibniz generally has not been considered a vital figure in the development of the way of ideas. Recent work on Leibniz, however, has introduced novel understandings of his theory. Benson Mates and Nicholas Jolley in particular have each argued on separate grounds that Leibniz thinks of ideas as mere dispositions. Although their analyses (rightly) do not push them to argue that Leibniz’s theory of ideas lies outside of the traditional ontology, the possibility remains that one might so argue. Therefore I engage in some preventative analysis in the fifth chapter by examining Leibniz’s theory, demonstrating that his innovations with respect to ideas remain within the traditional ontology.

The most important of the early moderns for this study is Berkeley, and thus his philosophy takes center stage. Trumpeted by several scholars as representing the final break from the traditional ontology of ideas, Berkeley is often said to be the key philosopher who completes the transition to epistemology as first philosophy. Such scholars do not assert that Berkeley lacks a metaphysical system; instead, the claim is that Berkeley’s theory of ideas liberates them (ideas) from the confines of ontology entirely. Consequently it is particularly important to resist the trend in contemporary scholarship toward the early modern tale with respect to Berkeley.

In the sixth chapter I seek to establish that although Berkeley did stretch the traditional ontology of substance and mode by introducing a new category for ideas, he did so as part of an attempt to preserve that basic ontology. Careful investigation of Berkeley’s texts reveals that he thinks that ideas are like modes in that they are essentially dependent beings but that they are also like substances insofar as they are distinct from the minds on which they depend without being modifications of them. They thus have characteristics of both substances and modes, requiring the positing of a new hybrid ontological category I call quasi substance. Mine is, of course, a controversial reading of Berkeley that has important consequences for the rest of his philosophical system. Nonetheless, I argue that there is significant textual and philosophical evidence that pushes the careful reader of Berkeley to this conclusion.

In order to more thoroughly defend this reading of Berkeley’s theory of ideas, I explore some of its consequences. In the seventh chapter I apply this understanding of ideas to his much-maligned theory of divine ideas, demonstrating that there is a plausible and textually consistent reading of the theory. Divine ideas, like ideas generally, are quasi substances in that they depend on the mind of God for their existence but also are nonetheless distinct from (i.e., not a part of) God’s mind. This move allows Berkeley to employ the theory of divine ideas to solve a wide range of problems, especially those concerning our perception of a continuous and unfragmented world, without it producing disastrous conflicts with the rest of his metaphysics. Given the demands of philosophical charity and the benefits that emerge from my reading, I conclude that we have excellent evidence to read Berkeley in this way.

The eighth chapter takes up two additional important features of Berkeley’s metaphysics and applies my new interpretation of his ideas to them. First, I seek to reconcile his theory of ideas with his rejection of abstract ideas. When we understand that Berkeley considers ideas to be distinct from minds but also dependent on them, we discover a new and more compelling reason for him to dislike abstraction. Abstract ideas, again like ideas generally, must be entities that exist in a two-place relation with the mind. Thus, in one important sense, ideas are “external” to the mind. They are neither modes of the mind nor parts of it. As such, abstract ideas are particular entities. Berkeley holds the not unreasonable view that all particulars must be fully determinate. That is, for every property, a particular existing thing must either have that property or its complement. There are no such things as particular objects that are indeterminate with respect to their properties. As a result there can be no such things as abstract ideas, which are described by Locke and others as ideas (things) that are indeterminate with respect to at least one property. Thus my reading of Berkeley has the additional virtue of providing a more charitable understanding of Berkeley’s resistance to the existence of abstract ideas.

Second, and still in the eighth chapter on Berkeley, I engage his controversial heterogeneity thesis. Berkeley alleges that we do not see the very same objects we feel. More generally, the objects of any one particular sense modality are different in kind from those of every other sense modality. The moderns, however, inherited the concept of common sensibles from Aristotle, where one particular object is perceived by multiple sense modalities. Berkeley accordingly denies what was a commonly held and intuitive position about sensible objects. The main oddity surrounding the heterogeneity thesis is not the veracity of the claim itself but instead why Berkeley came to be such an apparently passionate advocate of it. Here I provide an explanation that again relies on the (ontological) nature of ideas developed in chapters 6 and 7. After considering and rejecting the main rival accounts, I argue that Berkeley’s overidentification of the content of ideas with their ontological status explains the depth and certainty of his conviction that ideas are heterogeneous.

The ninth and final chapter examines Hume’s ontology of perceptions. Frequently read as abandoning the concept of substance, or as at least relegating the concept to the bin of meaningless terms, Hume is often placed alongside Berkeley as a philosopher who “deontologized” ideas. Like Locke, Hume was not specifically interested in many ontological themes; nonetheless, that his focus was elsewhere does not entail that he thought ideas lacked an ontological foundation. Contrary to the anti-ontological tradition, I argue that Hume fairly straightforwardly thought of perceptions as traditional substances. That said, he also believed that the notion of substance was conceptually thin. That is, learning that perceptions are substances does not do much work in any philosophical system. I maintain that Hume was driven by the same sorts of concerns as Berkeley and demonstrate that he never abandoned the traditional ontological categories with respect to perceptions. Reading Hume as a philosopher minimally sensitive to certain metaphysical concerns actually helps us make better sense of his recantation in the appendix of the Treatise and helps us resolve other textual difficulties in his philosophy. My engagement of Hume is admittedly controversial but arguably provides him with a more consistent and plausible system.

The lesson from our extended engagement with Berkeley and Hume is twofold. First, neither Berkeley nor Hume can properly be understood outside the constraints of their ontological commitments. And because of their ontological commitments neither can play their assigned role in the early modern tale. Each is a philosopher thoroughly in the grips of the early modern ontology. Berkeley is most clearly a traditional idea metaphysician, despite developing an unusual hybrid ontological category. Second, an unreflective adherence to the early modern tale may blind us to some of the insights of the early moderns, obscuring these thinkers’ philosophical power. In particular, accepting the tale makes it more difficult to be charitable to them, especially Berkeley, in a historically sensitive way. The early moderns are of both historically antiquarian and genuinely philosophical interest. Diligently pursuing the moderns charitably reveals in a particularly clear way the poverty of the early modern tale.

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