A Companion to Rationalism E-Book

• Herausgeber: John Wiley & Sons
• Kategorie: Geisteswissenschaft
• Serie: Blackwell Companions to Philosophy
• Sprache: Englisch

Seitenzahl: 1348

Veröffentlichungsjahr: 2012

Beschreibung

This book is a wide-ranging examination of rationalist thought in philosophy from ancient times to the present day.

• Written by a superbly qualified cast of philosophers
• Critically analyses the concept of rationalism
• Focuses principally on the golden age of rationalism in the seventeenth and early eighteenth centuries
• Also covers ancient rationalism, nineteenth-century rationalism, and rationalist themes in recent thought
• Organised chronologically
• Various philosophical methods and viewpoints are represented

Leseprobe

Contents

Cover

Half Title page

Title page

Copyright page

Dedication

Contributors

Acknowledgments

Abbreviations

Introduction

Part I: The Core of Rationalism

Chapter 1: The Rationalist Impulse

I

II

III

IV

V

Chapter 2: The Rationalist Conception of Substance

Two Philosophical Impulses

Substance

The Empiricists on Substance

Descartes on Substance

Spinoza on Attribute

The Subjective Interpretation

The Objective Interpretation

Gueroult

OI and SI

Descartes and Spinoza

References and Further Reading

Chapter 3: Rationalist Theories of Sense Perception and Mind–Body Relation

Sense Perception as a Natural Process

Metaphysical, Epistemological, and Functional Aspects of Perception

Sense, Mind, and Knowledge in Seventeenth-Century Rationalism

Notes

References and Further Reading

Chapter 4: Rationalism and Education

References and Further Reading

Part II: The Historical Background

Chapter 5: Plato’s Rationalistic Method

Preliminaries

The Elenchos

The Method of Hypothesis

The Method of Dialectic

Conclusion

References and Further Reading

Chapter 6: Rationalism in Jewish Philosophy

The Interpretation of Scripture

Reason and the Law

Reason and Happiness

The Spinozistic Denouement

References and Further Reading

Chapter 7: Early Modern Critiques of Rationalist Psychology

Epicurean Empiricism

Critiques of Cartesianism

Conclusion

References and Further Reading

Chapter 8: Rationalism and Method

The Philosophical Background to Method

Descartes’ Method

Descartes’ Successors: Malebranche and Spinoza on Method

References and Further Reading

Chapter 9: Cartesian Imaginations: The Method and Passions of Imagining

The Status of the Rationalist Image

The Deeper Background

Descartes: The Directed Imagination of Mathematics, and Passions as Nascent Images

Malebranche

Conclusion

References and Further Reading

Part III: The Heyday of Rationalism

Chapter 10: Descartes’ Rationalist Epistemology

Descartes on Innateness

Two Rationalist Doctrines

The Methodical Case for the Two Rationalist Doctrines

Acknowledgments

Notes

References and Further Reading

Chapter 11: Rationalism and Representation

The Falsity Inherent in Sensory Ideas

Descartes, Arnauld, and the Notion of Material Falsity

Some Leading Interpretations

A New Interpretation

Conclusion

Acknowledgments

Notes

References and Further Reading

Chapter 12: The Role of the Imagination in Rationalist Philosophies of Mathematics

Introduction

Plato’s Divided Line and Mathematical Cognition

The Cartesians and the Problem of Pure Thought

Descartes on the Role of the Imagination in Forming a Distinct Idea of Corporeal Nature

Malebranche on the Role of the Imagination in Mathematical Cognition

Conclusion

References and Further Reading

Chapter 13: Idealism and Cartesian Motion

Cartesian Motion

Classical Problems

Realist and Idealist Resolutions

Conclusion

Acknowledgments

References and Further Reading

Chapter 14: Leibniz on Shape and the Cartesian Conception of Body

The Imaginary Status of Shape: The “Diachronic” Argument

The Dominant Synchronic Argument

An Alternative Interpretation

Shape and Idealism

Acknowledgments

References and Further Reading

Chapter 15: Leibniz on Modality, Cognition, and Expression

Notes

References and Further Reading

Chapter 16: Rationalist Moral Philosophy

Introduction

Descartes’ Ethics

Spinoza’s Ethics

Leibniz’s Ethics

Conclusion

References and Further Reading

Chapter 17: Spinoza, Leibniz, and the Rationalist Reconceptions of Imagination

Spinoza and the Passionate Imagination

Leibniz and the Logic of Imagination

Wolff and the Scholasticism of Imagination

Conclusion

References and Further Reading

Chapter 18: Kant and the Two Dogmas of Rationalism

I

II

III

IV

V

References and Further Reading

Part IV: Rationalist Themes in Contemporary Philosophy

Chapter 19: Rationalism in the Phenomenological Tradition

The Emergence of Phenomenology Amid Varieties of Rationalism

Phenomenology in Brief

From Logic to Phenomenology

A Phenomenological Theory of Knowledge

Intuition of Essences

Intuition of Meanings

A Phenomenological Critique of Empiricism and Rationalism

References and Further Reading

Chapter 20: Rationalist Elements of Twentieth-Century Analytic Philosophy

I

II

III

IV

Notes

References and Further Reading

Chapter 21: Proust and the Rationalist Conception of the Self

Introduction

I

II

Notes

References and Further Reading

Chapter 22: Rationalism in Science

The New Experimental Science as a Challenge to Intuition

Geometry and Intuition

The Mathematical Tradition and Theoretical Science

Notes

References and Further Reading

Chapter 23: Rational Decision Making: Descriptive, Prescriptive, or Explanatory?

Introduction: Rational Decisions as an Ideal

Rational Decision Making?

Assumptions and Difficulties: Preferences, Outcome Spaces, and Probabilities in the World

Reasons without Decisions

What Kinds of Reasons? The Failure of RCT as a Unifying Principle

The Failures of RCT and Rethinking Rationality

References and Further Reading

Chapter 24: What is a Feminist to do with Rational Choice?

Introduction

Rational Choice

Moral Philosophy

Science of Human Behavior

Back to Moral Philosophy

Rational Choice, Finally

Against Orthodoxy

Public and Private

Notes

References and Further Reading

Chapter 25: Rationalism in the Philosophy of Donald Davidson

Introduction

Rationalism and the Analytic/Synthetic Distinction

A priori Principles I: Davidson on Causation and the Mental

Constitutive Principles and Classical Rationalism

Classical Rationalism or Kantian Transcendentalism?

The Refutation of (Transcendental) Idealism

Rationalism Full-Blown

Notes

References and Further Reading

Index

A Companion to Rationalism

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A Companion to Plato

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This paperback edition first published 2013 © 2013 by Blackwell Publishing Ltd except for editorial material and organization © 2013 by Alan Nelson

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Library of Congress Cataloging-in-Publication Data

A companion to rationalism / edited by Alan Nelson. p. cm. – (Blackwell companions to philosophy) Includes bibliographical references and index. ISBN 978-1-4051-0909-3 (pbk. : alk. paper) – ISBN 978-1-118-36062-0 (pbk. : alk. paper) 1. Rationalism. I. Nelson, Alan Jean. II. Series. B833.C66 2006 149’.7–dc22 2005010996

A catalogue record for this title is available from the British Library.

To Linda and Ian with love

Contributors

Henry E. Allison is Research Professor of Philosophy at the University of California, Davis.

Hugh H. Benson is Professor and Chair of Philosophy at the University of Oklahoma.

Timothy Crockett is Assistant Professor of Philosophy at Marquette University.

David Cunning is Associate Professor of Philosophy at the University of Iowa.

Gary Hatfield is the Adam Seybert Professor in Moral and Intellectual Philosophy at the University of Pennsylvania.

Jonathan Michael Kaplan is Associate Professor of Philosophy at Oregon State University.

Matthew J. Kisner is Associate Professor of Philosophy at the University of South Carolina.

Thomas M. Lennon is Emeritus Professor of Philosophy at the University of Western Ontario.

Paul Livingston is Associate Professor of Philosophy at the University of New Mexico.

Antonia LoLordo is Associate Professor of Philosophy at the University of Virginia.

Richard N. Manning is Professor of Philosophy at the University of South Florida.

Steven Nadler is Professor of Philosophy at the University of Wisconsin-Madison.

Alan Nelson is Professor of Philosophy at the University of North Carolina, Chapel Hill.

Lex Newman is Associate Professor of Philosophy at the University of Utah.

Lawrence Nolan is Professor of Philosophy at California State University, Long Beach.

Dennis L. Sepper is Professor of Philosophy at the University of Dallas.

David Woodruff Smith is Professor of Philosophy at the University of California, Irvine.

Kurt Smith is Associate Professor of Philosophy at Bloomsburg University of Pennsylvania.

Alice Sowaal is Associate Professor of Philosophy at San Francisco State University.

David Stump is Professor of Philosophy at the University of San Francisco.

Mariam Thalos is Professor of Philosophy at the University of Utah.

Andrew Youpa is Associate Professor of Philosophy at Southern Illinois University, Carbondale.

Acknowledgments

I thank the authors and the editors at Blackwell Publishing for making this volume possible. The final stage of my own editorial contributions was supported by a leave from the University of California, Irvine; and by the hospitality of the Philosophy Department at the University of North Carolina, Chapel Hill, and the Center for Human Science, Chapel Hill.

Abbreviations

Works cited frequently throughout the volume are abbreviated as follows:

A

Leibniz,

Sämtliche Schriften und Briefe

(Deutsche Akademie der Wissenschafter, ed.). Darmstadt: Akademie-Verlag, 1923–. Cited by series, volume, and page.

AG

Leibniz,

Philosophical Essays

(Roger Ariew and Daniel Garber, trans. and eds.). Indianapolis, IN: Hackett, 1989.

AL

Bacon,

The Advancement of Learning.

In Brian Vickers (ed.),

Francis Bacon: A Critical Edition of the Major Works.

Oxford: Oxford University Press, 1996. Cited by page.

Ar

Aristotle,

De Anima

(J. A. Smith, trans.). In J. Barnes (ed.),

Complete Works of Aristotle

, 2 vols. Princeton, NJ: Princeton University Press, 1984. Cited by the standard page and line numbers for Aristotle’s works (Bekker numbers).

AT

Descartes,

Oeuvres de Descartes

, 11 vols. (C. Adam and P. Tannery, eds.). Paris: Librairie Philosophique J. Vrin, 1996.

C

Leibniz,

Opuscules et fragments inédits de Leibniz

(L. Couturat, ed.). Paris: Presses Universitaires, 1903.

CSM

Descartes,

Philosophical Writings

, 2 vols. (J. Cottingham, R. Stoothoff, and D. Murdoch, trans.). Cambridge: Cambridge University Press, 1984–5. Cited by volume and page number.

CSMK

Descartes,

Philosophical Writings, Vol. 3: Correspondence

(J. Cottingham, R. Stoothoff, D. Murdoch, and A. Kenny, trans.). Cambridge: Cambridge University Press, 1991.

DG

Descartes,

The World and Other Writings

(S. Gaukroger, trans.). Cambridge: Cambridge University Press, 1998.

DM

Leibniz,

Discourse on Metaphysics.

In C. J. Gerhardt (ed.),

Die philosophischen Schriften von G.W. Leibniz

, 7 vols. Hildescheim: Olms, 1965. Cited by article number.

G

Leibniz,

Nouvelles lettres et opuscules inédits de Leibniz

(Foucher de Careil, ed.). Paris: Auguste Durand, 1857.

GM

Leibniz,

Leibniz’ Mathematische Schriften

(C. I. Gerhardt, ed.). Berlin: A. Asher; Halle: H. W. Schmidt, 1849–63. Cited by volume and page.

GP

Leibniz,

Die philosophischen Schriften von Gottfried Wilhelm Leibniz

(C. I. Gerhardt, ed.). Berlin: Weidmann, 1875–90. Cited by volume and page.

JS

Malebranche,

Dialogues on Metaphysics and on Religion

(N. Jolley and D. Scott, trans.). Cambridge: Cambridge University Press, 1997.

Le Grand

Antoine Le Grand,

An Entire Body of Philosophy According to the Principles of the Famous Renate Des Cartes

, 2 vols. (R. Blome, trans.). London: Samuel Roycroft, 1694. (Reprint, New York: Johnson Reprint, 1972.)

LL

Leibniz,

Philosophical Papers and Letters

(L. E. Loemker, trans.). Dordrecht: Reidel, 1969.

LNE

Leibniz,

New Essays on Human Understanding

(P. Remnant and J. Bennett, trans.). Cambridge: Cambridge University Press, 1981.

M

Leibniz,

The Leibniz Arnauld Correspondence

(H. T. Mason, trans. and ed.). Manchester: Manchester University Press, 1967.

Mal

Malebranche,

The Search after Truth

(T. M. Lennon and P. J. Olscamp, trans.). Cambridge: Cambridge University Press, 1997.

NO

Francis Bacon,

Novum Organum.

Cited by section.

OC

Malebranche,

Oeuvres complètes de Malebranche

, 20 vols. (A. Robinet, ed.). Paris: J. Vrin, 1958–67.

P

Leibniz,

Leibniz: Philosophical Writings

(G. H. R. Parkinson, ed., M. Morris and G. H. R. Parkinson, trans.). London: Dent, 1973.

QNS

Francisco Sanchez,

Quod Nihil Scitur

(D. Thomson, trans.; introduction, notes, and bibliography by E. Limbrick). New York: Cambridge University Press, 1988. Cited by page.

RA

Leibniz,

The Labyrinth of the Continuum: Writings on the Continuum Problem, 1672–1686

(R. T. W. Arthur, trans. and ed.). New Haven, CT: Yale University Press, 2001.

RB

Leibniz,

New Essays on Human Understanding

(P. Remnant and J. Bennett, eds. and trans.). Cambridge: Cambridge University Press, 1981.

Régis

Pierre Régis,

Cours entier de philosophie, ou systeme general selon les principes de M. Descartes,

Latest Edition, 3 vols. [Entire Course of Philosophy, or General System According to the Principles of Mr. Descartes]. Amsterdam: Huguetan, 1691. (Reprint, New York: Johnson Reprint, 1970.)

Rohault

Jacques Rohault,

System of Natural Philosophy

, 2nd edn. (J. Clarke, trans.). London: Knapton, 1728–9. (Reprint, New York: Garland, 1987.)

SE

Spinoza,

Ethics.

In E. Curley (ed. and trans.),

Collected Works of Spinoza

(pp. 401–617). Princeton, NJ: Princeton University Press, 1985. Cited by Part, Proposition, and Note.

Search

Malebranche,

The Search After Truth

(T. M. Lennon and P. J. Olscamp, trans.). Columbus: Ohio State University Press, 1980.

TEI

Spinoza,

Treatise on the Emendation of the Intellect.

In S. Feldman (ed.) and S. Shirley (trans.),

Ethics, Treatise on the Emendation of the Intellect and Selected Letters.

Indianapolis, IN: Hackett, 1992. Cited by page and line number.

TTP

Spinoza,

Theological-Political Treatise.

In C. Gebhardt (ed.),

Spinoza Opera.

Heidelberg: Carl Winter, 1925. Cited by volume and page.

Introduction

What is rationalism? Philosophers have learned not to expect detailed, or even fully coherent, answers to this sweeping kind of question. There is, nevertheless, a core of rationalist thinking that can be traced through two millennia of recorded philosophical development. The rationalist insists on the distinction between appearance and reality. Reality is revealed to our rational thought, which might also be called “reason” or “intellect.” Since appearance is the way reality appears to us, philosophy has two important tasks. The first is to employ rational thought to reveal the truth about the real. The second is to explain the appearances in terms of the real. Why do we naturally fasten on apparent truth instead of the real? Why must the real appear as it does when our rationality is not specially applied to it? Most rationalists want the appearances to be explained as necessary consequences of the human condition.

The central example of this philosophical attitude is the explanation of sense perception. Our sensing something to be colored red is treated as depending on something that is ultimately not red – not really red – perhaps particles of light affecting our sense organs. This provides a fairly neat and iconic contrast with empiricism, the complement of rationalism. The empiricist takes sensory information as prior to, and providing data for, explanatory hypotheses. The role of these hypotheses is to classify, simplify, and interrelate the data. There is no sense in which the hypotheses are more true or real than appearances for the empiricist.

The chapters in part one of this book, “The Core of Rationalism,” explore these fundamental features of rationalism. “The Rationalist Impulse” explores the attitudinal differences between rationalist and empiricist philosophy. “The Rationalist Conception of Substance” tracks the development of that crucial element of rationalist reality with a particular focus on Spinoza, who made it central in his philosophy. “Rationalist Theories of Sense Perception and Mind–Body Relation” examines explanations of how appearances come to the mind through the body’s sense organs and how this relates the appearances to reality so that they can be used as part of the quest for truth. Finally, the philosopher’s path from a childhood immersed in the senses to a sagacious adulthood and how rationalists try to bring their readers along this path is the topic of “Rationalism and Education.”

The chapters in part two, “The Historical Background,” take us from the beginnings of theoretical rationalism up until the great flowering of rationalist thought in the seventeenth century. Plato is the iconic rationalist, though “Plato’s Rationalistic Method” brings out some of the problems in making this characterization precise. An important link between the ancients and Spinoza is forged by focusing on medieval rationalism in the Jewish tradition in “Rationalism in Jewish Philosophy.” One of the great critics of early modern rationalism was Pierre Gassendi, who championed an updated understanding of ancient anti-rationalist atomism. The chapter “Early Modern Critiques of Rationalist Psychology” puts Gassendi’s critique of rationalist theories of sense perception into the context of the intense debates sparked by Descartes’ rationalism. Another aspect of these debates was concerned with the new stress on method in philosophical and scientific thinking. The development of Descartes’ canonical statement of the rationalist side of this story is the main topic of “Rationalism and Method.” The distinction between passive sensation and active reasoning is central to the history of Rationalism. This distinction is richly elaborated by the consideration of imagination, which is naturally understood as the active combination of elements passively received in sensation. “Cartesian Imaginations: The Method and Passions of Imagining” follows the development of this theme into the seventeenth century and the transformation of the role assigned to imagination in Descartes and his followers.

The chapters in part three, “The Heyday of Rationalism,” examine rationalism as it appears in the works of the great canonical figures formerly known as the Continental Rationalists. “Descartes’ Rationalist Epistemology” analyzes the distinction between knowledge that is transmitted via the senses and knowledge that is innate to the mind. Because the treatment is in the context of Descartes’ philosophy, his famous method of doubt also comes under scrutiny. This critical distinction is developed in the context of the notion of mental representation in “Rationalism and Representation.” We return to the delicate issue of imagination in “The Role of the Imagination in Rationalist Philosophies of Mathematics.” Much depends on mathematics in Cartesian systems because of the identification of the essence of matter with the subject matter of geometry – extension in length, breadth, and depth. This means that the foundation of physics is geometry; this is one version of scientific mechanism. “Idealism and Cartesian Motion” is devoted to the various conceptual problems inherent to this part of Cartesianism. Leibniz’s critique of this conception of matter and his own Rationalistic approach to solving the problems is the subject of “Leibniz on Shape and the Cartesian Conception of Body.” His rationalism is considered in a more general framework in “Leibniz on Modality, Cognition, and Expression.” The great rationalists insisted that their philosophical thought, even the natural philosophical part of it (what we now call physics) was in the service of the development of moral philosophy. Spinoza’s great work was, of course, entitled Ethics. “Rationalist Moral Philosophy” addresses some of the most salient considerations. We return to the hybrid faculty of imagination in “Spinoza, Leibniz, and the Rationalist Reconceptions of Imagination,” which brings the story up to some of the pressures that lead from Leibniz through Wolff to Kant. Finally, “Kant and the Two Dogmas of Rationalism” is a critical examination of Kant’s engagement with rationalist theories of truth and of the contrast between sensory and intellectual knowledge.

The chapters in part four, “Rationalist Themes in Contemporary Philosophy,” study how both the core issues and transformations of them remain alive in more recent thought. Indeed, there are some ways in which traditional rationalist themes are very much alive even in contemporary philosophy. All of these chapters, however, also serve to bring out how it is ultimately problematic to distinguish sharply between rationalism and empiricism. “Rationalism in the Phenomenological Tradition” explicitly puts into the historical tradition the phenomenology of Husserl and later phenomenological research in the important Husserlian tradition. “Rationalist Elements of Twentieth-Century Analytic Philosophy” does the same for another, even more dominant twentieth-century philosophical tradition; here we find a particular focus on the development from the early Russell to Carnap. “Proust and the Rationalist Conception of the Self” makes a case that the great novelist represents one culmination of rationalist theorizing about self and identity. Rationalism in its seventeenth-century heyday was animated by the ideal of providing rationalist foundations for modern science. “Rationalism in Science” traces this theme up to the present day. “Rational Decision Making: Descriptive, Prescriptive, or Explanatory?” is an explanation and also an internal critique of contemporary rationalism with respect to action and choice. “What is a Feminist to do with Rational Choice?” is a more external critique that raises important questions about hidden presuppositions. Finally, “Rationalism in the Philosophy of Donald Davidson” shows how the distinction between rationalism and empiricism plays out in one of the most influential systems of philosophical thought in contemporary philosophy.

Part I

THE CORE OF RATIONALISM

Chapter 1

The Rationalist Impulse

ALAN NELSON

Philosophers are rightly suspicious of the usefulness of broadly conceived labels and “-isms.” They are particularly suspicious when the labels mark dichotomies. Rationalism thus qualifies as suspicious if it is taken to be a neatly delineated set of doctrines. The task assumed by this chapter is not to find such a set, but instead to provide an analysis of what I shall call the impulse to philosophize rationalistically. The analysis therefore does not purport to sharply distinguish a set of maxims or propositions characteristic of rationalism from another set proper to its foil, empiricism. Nor does it attempt to delineate specific doctrines to which all “rationalists” adhere. I shall, however, argue that attention to some overarching themes in rationalist systems of philosophy can be of considerable use in understanding the philosophical accomplishments of the great rationalists. Insufficient attention to these themes has often led to interpretations of rationalists that skew the dialectic with their empiricist antagonists in favor of the latter.

I shall draw some examples from Plato, who provides most of the earliest texts clearly articulating rationalist themes. The primary focus will be on the great thinkers from the seventeenth-century heyday of rationalism, but in conclusion some observations will be made about the rationalist impulse in Russell’s logical atomism. This should help bring into relief some respects in which the triumph of empiricist sensibilities among historians of philosophy in the twentieth century and beyond has made the rationalist impulse rather alien. Naturally, this is not conducive to recovering the spirit of rationalist projects.

I

The primary and customary sense of the term “rationalism” characterizes a philosophical attitude toward knowledge. Knowledge itself is partly characterized both by the subjects, or possessors, of knowledge and by the objects of knowledge, the things to be known. Rationalism, therefore, bears on ontology since it requires an understanding of the natures of these subjects and objects. There are also characteristically rational processes or techniques for obtaining or developing knowledge, so rationalism bears on method, philosophical education, and the nature of philosophy itself.

The traditional series of contrasts with its foil, empiricism, thus begins with subjects and objects of knowledge. Traditional rationalisms identify the intellect, the mind, or the rational part of the soul (or even the State) as of primary importance in receiving and holding knowledge. The corresponding objects of knowledge are then non-sensory, general, and unchanging or eternal. Traditional empiricisms, by contrast, identify the senses, or common sense, or the sensitive part of the soul as of primary importance. The corresponding objects of knowledge are then the inhabitants of the temporal world in flux. Of course, rationalists have a story to tell about how some kinds of derivative knowledge depend directly on the senses. We can come to know that the senses are reliable indicators of what is beneficial to us and we can then know (as opposed to taking it for granted) that, for example, bread nourishes. Furthermore, absolutely all knowledge depends in some attenuated ways on the sensory because we need to learn more esoteric truths by first hearing or reading things that bring us to understand them. Empiricists similarly have a story to tell about the role of the non-sensory. The clearest example is Locke’s essential reliance on innate operations of the mind. This is an extreme case, but all empiricists need to have some account of how abstract, general truths are derived from what is given by the senses.

These points are crucial to appreciating the depth of the chasm between rationalism and empiricism despite the pockets of shared concerns and overlap. It is easy to see that the empiricist has an initial debater’s advantage. Because human beings are born helpless, pre-linguistic, and dependent, they first become cognizant of the sensory qualities of objects familiar to common sense. A normal person not having a prior education in rationalist philosophy will cling to thoughts of these familiar things when beginning a philosophical education. Thus the empiricist finds a ready pupil, an ally in fact, in what we now like to call the “untutored common sense” of a “sensible” person or a person of “good sense.” Such a person is apt to appreciate an analysis of features of the intangible, vaguely perceived, intellectual objects of rationalist knowledge into commonsensical items and their features. The rationalist teacher cannot display the reward of hard study to the beginning student like candy in a jar. Students are instead told that their opinions, while perhaps of considerable utility, are strictly speaking false and that the truth can be only vaguely characterized until they can see it for themselves. And the goal is to see the truth. Not visually, of course, but with the mind’s eye, through a “purely mental scrutiny” as Descartes put it.

II

How is the esoteric truth of the rationalist to be accessed? If mere exhortation is the last resort, even open-minded students will be justifiably suspicious. And even those who are somehow moved to appreciate the truth by exhortations might be later persuaded by other, contrary doctrines. What is required is some technique or method for bringing the student from a starting place favoring empiricism to the truth. An effective method must start with easy steps and progressively draw the pupil away from sensory distractions. Let us consider examples with some detail.

A rudimentary development of such a method can be found in Plato’s dialogue, Symposium (210a–212b). Here, the esoteric truth to be sought is described as a “vision” of Beauty itself, the Platonic form. Love is characterized as desire, ultimately desire for Beauty. The method, then, can be regarded as instruction in the art of loving well. The first step in this form of Platonic education requires that one love a beautiful body. This is ingeniously designed to be an easy step that requires no prior commitment and no special effort from most students. Loving (that is, desiring) a beautiful body comes naturally to humans and can be mostly driven by sensual appetites. The Trojan horse, of course, is that the body is beautiful in a way that connects it, albeit distantly and vaguely, to the final goal of Beauty itself. The next step is to love many beautiful bodies and this is, unbeknownst to the pupil, loving the Beauty in all these bodies. The beginning students’ inability to understand fully their intermediate accomplishments is characteristic of rationalist enlightenment. As students progress, they typically will not fully understand the nature of the progress they have made, nor do they need to. It is the final goal that is important. So lovers of many bodies might conceive their achievement as the ability to love different kinds of corporeal beauty, but the already enlightened understand that those at the second step are loving Beauty despite its degradation by various corporeal guises.

In this course of instruction, students next progress to the love of individual souls, and then to what might be regarded as the soul of the State, its laws. This leads to love of various kinds of knowledge and then to the love of knowledge in general – philosophy. The Philosopher, having thus advanced through these stages of love, is prepared to catch glimpses of Beauty itself. One crucial aspect of this method is that those who completed the course of instruction are able to perceive in ways that are unavailable to the uninitiated. Even a generally competent adult immersed in the world of sense will be unable to perceive truth at will. The situation is quite analogous to the development that can be effected in sensory capacities. All wine might taste sour to the neophyte, but a trained wine taster might make very fine discriminations with some reliability. A symphony orchestra might sound like noise to a child or someone trained in another musical tradition and so on. It is to be expected, therefore, that if rationalists begin a lesson or an exposition with a plain statement of Truth, they will meet with skepticism and incomprehension.

An interesting feature of the method described in the Symposium is that it is much more than a means of acquiring some abstract doctrines. It also involves learning a way of life. Since the “bringing forth of beautiful ideas” is itself a high form of appreciating Beauty, the advanced philosopher is motivated to teach beginners. It is not expected that pupils go it alone. This makes progress highly contingent on the availability of suitable teachers. It also means that the process of education requires a very long-term, daunting initial commitment of time from the student. The search for a method of discovery with greater generality, reliability, efficiency, and power led Descartes to his infamous method of universal doubt. Descartes himself would, of course, be horrified by later use of the term “Cartesian Skepticism.” Universal doubt is meant to lead to “perfect knowledge” of the truth and it is for this reason that he calls it “methodical.” The various functions of the doubt include (a) withdrawal from the senses whose particular deliverances are most easily doubted, (b) a preemptive strike against later doubts; if the project begins with, and then overcomes a universal, all-inclusive doubt there is no room for subsequent second guessing of anything that emerges from the doubt, and (c) the imposition of a strict order on the acquisition of knowledge.

Insufficient attention has been given to Descartes’ emphasis on the importance of “philosophizing in the correct order.” One reason that universal doubt comes first in the order is that it establishes an order for the entire enterprise. The first positive result is the cogito, “I think, therefore I am,” or simply, “I think, I am.” Why is the cogito first? Not because it is the obvious place to begin philosophizing; no one before Descartes chose this point. Nor is the cogito first because of any special, mysterious fecundity to be found in it. In fact, though Descartes moves from the cogito to some very important results, everything beyond the most basic principles of knowledge depends on one’s being a human with sensation, memory, and imagination. And the idea that has foundational priority for knowledge is not of the self, it is of God. It is not even the certainty that attaches to the cogito that makes it first in the proper order. The tri-laterality of triangles is just as certain as the cogito. The cogito comes first because it is delivered by the universal doubt itself. Doubting is thinking, so given that one doubts, one must exist to doubt. The very fact that one is doubting does not inevitably draw the attention to triangles, squares, or anything else; doubting instead brings to mind that one is doubting.

Once it emerges that one’s own existence follows from the idea of oneself present when doubting, there is no way to proceed except to ask whether the existence of anything else at all follows from the ideas of the thinking thing. The pupil, now in the guise of a solitary, independent meditator (independent except for reading Descartes!), is inexorably led to the existence of God, the existence of extension, and finally to the existence of the self as an embodied, thinking thing. This procedure does not enable one to clearly state the Truth to the unenlightened any more than the “steps of love” from the Symposium. Descartes’ method is, however, designed to be implemented in a number of days rather than a number of years. The method itself is, moreover, something to be employed once in a lifetime of learning with perhaps brief annual checkups or refreshers. And unlike the method described by Plato, it can serve as a foundation for various pursuits.

It is not surprising to the historian that different versions of the Truth are attained by different rationalists. This provides empiricists with a justifiable basis for attacking the general procedures of rationalism notwithstanding the fact that empiricists agree among themselves no more than do rationalists. There are, however, significant generalizations to be made about the sorts of Truth that a rationalist education is supposed to reveal. Perhaps the most striking characteristic of rationalist truth is its simplicity. It is simple in the strict sense that it is undivided and indivisible. In case there are a modest number of separate truths, they are each simple in themselves.

III

The most prominent example of a simple rationalist truth is the idea of infinite being. Empiricists tend to believe that insofar as we can understand infinity at all, our concept of it must be constructed from ideas of finite things. And insofar as we can do that, the result will be complex and unclear relative to the ideas of finite things employed in its construction. Rationalists, by contrast, believe that the idea of the infinite is conceptually prior to ideas of the finite. This does not mean that infants think about the infinite before they think about the finite. The point is that finite things are to be philosophically understood as limitations of the infinite. One does not begin with the truth concerning the finite and work to extend these truths to the infinite. Instead the post-enlightenment beginning, the principle of philosophy proper, is the infinite. The task of philosophy, after the attainment of the simple truth, is discovering the truth about finite things by understanding the respects in which they are limitations of what is infinite.

For example, finite things are limited in their knowledge, their power, their creative activity, their temporal and spatial extent (at least in some rationalist accounts), their goodness, etc. Again, the rationalist will agree with the empiricist that learning to conceive infinity might involve first reflecting on the conceptions of finite things and then imagining the various limitations being removed, perhaps one by one. But once in command of the idea of infinity, the epistemic situation is reversed. The perfect wholeness and simplicity of the idea of the infinite must have limitations imposed upon it in thought to arrive at accurate conceptions of finite things. Spinoza expresses this by saying that finite things “follow” from the infinite and must be “conceived through” it.

A more specific example is provided once more by Descartes’ position on the nature of thought. Scholars have long debated whether Descartes is best interpreted as taking consciousness or intentionality as the fundamental core of thought. Others have disputed whether it is the intellect or the will that is more basic to the thinking thing. None of these discussions are Cartesian in spirit. Descartes makes it very clear that the essence of a thinking thing is to think. Thought itself is something as perfectly simple as a finite thing can be. The philosopher’s task is to explain the variety of phenomena, the empirical, given the simple idea of thought. This is the opposite of the empiricist’s task of searching for deep mysterious essences (often concluded to be inaccessible anyway) using commonsensical building blocks.

The principal theoretical device for explaining the appearance of diversity in what is really simple depends on being able to think identically the same ideas “under different aspects” or “regarding” them in different ways. Doing this is said to produce a distinction of reason, a conceptual distinction, or (especially appropriate in the present context) a rational distinction. So a Cartesian philosopher might regard the idea of himself as a finite thinking thing in various ways. He might regard the passive aspect of thought in which it perceives ideas of things, or instead he might regard its active aspect in which it chooses to attend to the apparent good. In this account, will and intellect are only rationally distinct. When one accurately perceives will or intellect one is in each case perceiving the same idea, the idea of finite thought albeit under different aspects. Similarly, perceiving omniscience and omnipotence is to perceive exactly the same thing, infinity, but under different aspects. Yet another example would be the perception of divisibility and quantity, which are both aspects of Cartesian extension. In each case, the simple ideas of infinity, thought, or extension are conceptually prior to the particular, rationally distinct aspects under which they might be regarded.

The notion of rational distinction itself was probably an invention of medieval philosophers attempting to explain the various ways in which the perfect simplicity of God is perceived. The device is particularly important in developing the rationalist impulse, but it is very important to note that empiricists also have occasion to put it to work. The arch empiricist Hume found it necessary to employ a version of the rational distinction to understand the comparisons between, for example, “figure and body figured; motion and the body moved” (A Treatise of Human Nature, 1.1.7). The only essential difference between Hume and Descartes on this point is that Hume takes sensory impressions to be prior to the abstract ideas in question, while Descartes would take these ideas to be distinct, “concrete,” and prior to their confused representation in the senses.

Although the centrality of the theory of rational distinction has not been much noted by scholars, its importance to rationalist philosophy cannot be overstated. After an education in rationalism has freed the philosopher from the prejudices of the senses and the truth is uncovered, that truth is revealed to be simple. For most rationalists, the truth available to human beings is expressed in a handful of innate ideas. The richness of human experience then needs to be explained as somehow arising from this source. Otherwise, rationalism would be reduced to either the inquiry-halting position of Zeno of Elea who taught that Being is an unintelligible, really undifferentiated unity, or else to a skeptical phenomenalism in which sensation is utterly unconnected with reality. Once it is understood that the appearances or phenomena of unschooled, everyday life are grounded in simple ideas expressing a Truth inaccessible to sensory investigation, the phenomena themselves appear in a new light to the rationalist. The appearances are transformed and reconfigured by the reality of which they are, after all, mere appearances.

IV

The rationalists’ reconfiguration of experience brings into sharp relief an important contrast with empiricism. For an empiricist, the ultimate test of the reasonableness, the credibility, and the fruitfulness of a philosophical theory is its conformity with appearances as experienced by common sense. It is fine to be told that the dog down the street is a machine, or an aggregate of monads, or a finite mode of the infinite, so long as one arrives at a deep analysis of what the dog really is. And the same holds for cookies, hands, the moral wrongness of taking candy from babies, and so on. A committed, theoretically minded empiricist might be prepared for thoroughgoing analyses, or even reductions, of all these items to esoteric theoretical entities. A cookie might be an aggregate of elementary particles, and the wrongness of an action might even reduce to something that is not intrinsically normative – say, Hume’s custom. What a certain kind of empiricist is not prepared to accept is that dogs, hands, taking candy from babies, etc. are not the touchstones, the base from which philosophical theorizing begins. For these empiricists, philosophical theories are to be judged according to the fidelity with which their analyses result in the furniture of the commonsense world. The rationalist, by contrast, discovers that the world of common sense is merely an appearance of what is real and true. So it is to be expected that dogs, hands, and the rest are not really precisely individuated.

The present point connects with the previous observations about rationalism. We first saw how the proper starting place for philosophical explanation is not ready to hand, but requires careful education. One must unlearn the apparent truths of common sense to gain an appreciation of where philosophy proper begins. Perhaps this is best expressed by saying that philosophy consists of two stages. The first stage is an unlearning of prejudice, a preparation for doing real philosophy. According to a rationalist, the empiricist attempts to do philosophy on the cheap without bothering to put in the requisite training. The empiricist is like the tennis player who wants to be a champion without practicing ground strokes or the pianist who wants to play Chopin without practicing scales. The second stage can only begin once an adequate understanding of the Truth is in place. The rationalist’s understanding of the Truth is, therefore, not rightly characterized as a “theory.” It is not a hypothesis supported by evidence. What might the evidence be except for the deliverances of the empiricist’s common sense? The Truth must instead come to be understood, appreciated, or “seen” by the knower’s innate attunement with it. This attunement must, of course, receive some explanation. But – and this is the sticking point – the explanation of attunement must itself proceed from the Truth as explanans.

We also saw that the rationalist’s Truth is relatively simple. Infinity, thought, and extension are simple in Descartes’ system, for example. And this simplicity means that they are easy to understand for the enlightened sage; a claim that provokes frustration or amusement from the empiricist. But given that the rationalist’s Truth is simple, the empiricist’s easily understood items – dog, hand, etc. – turn out to be fabulously complex in reality. This is not to deny that empiricists might welcome a theory which maintains that dogs are complexes of cells, or atoms, or impressions, or etc. It is instead characteristic of the empiricist to insist that what are really dogs can be given a theoretical analysis into theoretical simples. The theoretical entities cannot be more real than commonsensical objects because the latter are what ground the fallible postulation of the former.

V

Once the topic of the analysis of appearances has been raised in this way, it is natural to see how it is played out in philosophy that is analytic in a historically strict sense of the term. The issues arise clearly at the very beginning in the twentieth-century analytic philosophy of Russell and Moore. To standardize terminology we can say that this sort of analysis takes the objects of knowledge to be facts. Facts are symbolized or expressed by propositions. Analysis then consists in analyzing some propositions into others. For Moore, analysis typically begins with a proposition that we know to be true. Some of these propositions also have analyses that are known. We might know, for example, “T is an equilateral triangle” and know that this analyzes into “T is a closed, plane figure with three equal sides.” Philosophical analysis most typically involves cases in which we know the analysandum to be true, but do not know its correct analysis. A typical Moorean example is the proposition expressed by the sentence “I now see a hand before me” when one is looking at one’s own hand before oneself. Moore regards this as known for certain, but thinks the correct analysis is very hard to come by. At times he thought the first step in the analysis includes the proposition “‘This is seen by me’ and ‘This is part of the surface of a hand,’” but he was never sure of how to proceed. What I wish to stress here is that Moore begins by taking the deliverances of common sense as known for certain. Being in possession of correct analyses would somehow enhance this knowledge though Moore, with characteristic caution, was unsure of the nature of the enhancement. This is very much in the spirit of empiricism. Knowledge in philosophy derives from analyses of what is known for certain by common sense. Moore rejected outright the suggestion that an analysis of common sense could lead to knowledge that revealed common sense as false. That is, propositions expressing commonsensical truisms express facts, and these propositions cannot be discovered to be false because these facts are indisputable. This is the foundation of Moore’s famous “defense of common sense.” We know that any philosopher purporting to undercut common sense by showing propositions expressing commonsensical truisms to be false must have made a mistake in analysis.

Analysis in Russell’s logical atomism is different in character. He agrees with Moore that valuable philosophical analyses begin with things that we take for certainly true. Where else would we begin the quest for philosophical enlightenment – with things we regard as highly dubious? Russell believed, however, that sentences in natural language expressing commonsensical truisms are highly misleading in their logical form. Sentences like “Socrates was snub-nosed” or “The cat is on the mat” might appear to the uneducated to express simple facts about Socrates and the cat. We begin the analysis of such sentences by first translating them into a more appropriate symbolism. The full analysis of the sentences into a proposition with an appropriate logical form would reveal vast complexity, perhaps an infinite complexity. This is because the logical atoms which are the goal of the analysis must include names for logically perfect simples, items with no further structure whatsoever. These atoms are manifestly unavailable to common sense. They are, in fact, probably unavailable altogether although logical atomism holds by a kind of transcendental argument that they must be at the “ground floor” as a condition of the possibility of a symbolic system’s representing reality.

Russellian analysis thus displays some of the characteristic features of rationalism. Most prominent is its radical reconfiguration of common sense. Propositions that Moore knows to express facts are revealed under Russellian analysis to be vaguely and ambiguously expressed complexes of facts beyond the grasp of human intellect. So “Socrates,’” “snub-nosedness,” “the cat,” and “Piccadilly” all stand for logical constructions, and apparently well-formed propositions employing these symbols vaguely and ambiguously symbolize complexes of atomic facts. Russell, therefore, was prepared for analysis to reveal that such “things” as dogs, cats, mats, even persons, the “properties” of these things, and their ordinary activities are not fully real. (Or better, that they are not in the end constituents of facts.)

Russell himself does seem to have been inclined to think that the atomic facts contain as constituents something very much like Hume’s simple impressions and simple ideas. This reflects his sympathy with empiricism. In other places, he seems to regard it as no more than a hypothesis, or even an example of what the logical atoms might be like. So it seems to be the simplicity and indivisibility of the atoms that impressed Russell most and this is, as we have seen, guided by the rationalist impulse. To be sure, logical atomism results in a great many of the simples; in this respect it is more like Leibniz’s Monadology than like the systems of Descartes or Spinoza. Russell diverged from the more empirically minded Moore in laying heavy stress on the inadequacy of ordinary expressions in natural languages. For Russell, learning a system of symbols that reflected the structure of the esoteric atomic facts was a necessary prerequisite to effective philosophy. This might be seen as a version of the first of the three characteristics of rationalist thought discussed above; namely the requirement that the philosopher be trained to transcend the truths of common sense to appreciate an esoteric simple truth.

In short, Russell’s analytic philosophy, especially in this period of his development, was in crucial aspects aligned with mainline rationalism. Moore’s version of analysis was much more in line with traditional empiricism. It is interesting to observe that much contemporary analytic philosophy is done more in the spirit of Moore than in the spirit of Russell. When an analysis is controlled by, and ultimately answerable to, untutored “intuitions” about the commonsensical observations of “plain” people in Western cultures, that analysis is in an empiricist tradition.

Philosophers trained in these techniques might be in an excellent position to understand what the great, canonical empiricists were trying to do and how they viewed the philosophical enterprise. It might, however, be necessary for them to exercise particular caution when they turn to the interpretation of the rationalist tradition. Rationalist philosophy, like modern science, does not “leave everything as it is.” It is instead an adventure that transforms the philosopher’s perception of the world.

Chapter 2

The Rationalist Conception of Substance

THOMAS M. LENNON

Two Philosophical Impulses

Rationalism is often best understood against the foil of empiricism, for these two styles of philosophizing spring from very different philosophical impulses. Empiricists seek to know the way the world is. Their goal is to gather data, whether from controlled experiment or from hurly-burly experience, in order to produce a description of the world. The drift among them is away from the ideal of a single description of the world toward the acceptability of a multiplicity of descriptions, constrained only by pure pragmatics, to the point that whether there is one world, many worlds, or none at all answering to their describing makes no difference.

By contrast, rationalists already know the way the world is. Recall Plato and his doctrine of learning as reminiscence, but also Descartes, who, in ruminating on the essence of material things, finds his discovery of the truth he discovers “not so much learning something new as remembering what I knew before” (Descartes 1985b: 44). Rationalists instead seek to know why the world must be the way it is. Their theories are thus prescriptive instead of descriptive. Descartes, in asserting that existence is inseparable from God, makes clear that the modal terms he employs are based in objective features of the world. “It is not that my thought makes it so, or imposes any necessity on anything.” (This sort of imposition by the mind would be what Leibniz called the super-nominalism of Hobbes, whom Descartes summarily dismisses (Descartes 1985b: 135–6), or of Locke, for whom the essences of things, or the kinds to which they belong, depend on our ways of sorting them.) “On the contrary,” Descartes continues, “it is the thing itself, namely the existence of God, which determines my thinking in this respect” (Descartes 1985b: 46). Necessity imposes itself on the mind by prescribing the way it must think about the world.

If the underlying impulse of rationalists, prior to all argument, is the visceral conviction that the world could not have been otherwise, the empiricists’ conviction is that the world inexplicably just is the way it is. Thus the defining commitment of empiricism to experience as the ultimate source of all knowledge is in fact posterior to its initial impulse. Experience of the world is needed because reason does not tell, or is not told, why it must be as it is. An additional part of the empiricist conviction is that the world is multiple, diverse, and complex. There are many things in the world, they differ in many ways, and it is not clear how they relate to one another. So much is revealed by experience, which then becomes the only basis for dealing with such a world.

The rationalist impulse is in response to a perceived unity, uniformity, and simplicity in the world; to rationalists, the world seems to hang together and form a coherent whole. This simplicity and unity provide the ground for necessity insofar as what is said (or thought) about the world is said (or thought) about a single thing. Truth, as Leibniz insisted, is ultimately a matter of identity, even if the identities that we finite minds are able to demonstrate are limited to those that hold in all possible worlds (such would be the truths of logic and mathematics). Those truths that hold only in this actual world (factual truths such as that Caesar crossed the Rubicon, for example) are also identities; but they are known as such only to God’s infinite mind. Leibniz himself thought that these identities are individually true of a multiplicity of objects, but the implicit tendency in his thought, and certainly among the rationalists generally, is toward a single object. A fragment from the ancient Greek poet Archilochus has it that the fox knows many things, but the hedgehog knows one big thing. The empiricists are foxes, the rationalists hedgehogs.

A good model for this initially bizarre view that there is but one object to be known is the fairly intuitive proposition 5 from book 1 of Euclid’s Elements, namely, that the base angles of an isosceles triangle are equal. Euclid’s proof is rather complicated, relying on additional construction. Pappus avoided this complication with a very simple proof: “let us conceive this one [isosceles] triangle as two triangles … all the corresponding parts (in the triangles) are equal, including the two equal sides and the angle between them, and therefore [as proven by proposition 4] the angles subtended by the equal sides, which are the base angles of the triangle.” But what of the two triangles? According to the classic commentary of Thomas Heath, “we may answer we keep to one triangle and merely view it in two aspects. If it were a question of helping a beginner to understand this, we might say that the one triangle is the triangle looked at in front and that the other is the same triangle looked at from behind; but even this is not really necessary” (Euclid 1956: 254). To put it another way, constructing an isosceles triangle just is to construct a triangle whose base angles are equal, and to think about the one is to think about the other, albeit in a different way, for they are the same thing. What is true of this knowledge of isosceles triangles is true of all the others of Euclid’s demonstrations, which from a rationalist perspective are so many dispensable heuristics whose function is to bring us to the perception of the single object. And what is true of geometrical knowledge is, according to this rationalist thinking, true of all our knowledge.

This model for knowledge as rationalists conceive it is very important and will often be referred to below. Reference will be made easier by a name for it: the sub specie (“under the aspect of”) model. Knowledge is a matter of making necessary connections, which we are able to do because we are viewing the same thing under different aspects. The world must be the way it is for the same sort of reason that the base angles of an isosceles triangle are equal. This is the basis for the putative unity, uniformity, and simplicity of the world.

The principal aim of this chapter is to show how this model might be of use at three interconnected levels: first, in understanding how some of the major rationalists thought about basic issues; secondly, in understanding some of what has been written about what they thought; and thirdly, in understanding some of the apparent differences in how the major rationalists thought. At the first level is rationalist thought about substance; at the second is the dispute in the literature over Spinoza’s conception of an attribute and its connection with substance; thirdly, there is the question of how Spinoza differed on this issue from Descartes.

However much the sub specie model might be reflected in rationalist thinking, that model is only a model. For the world is not an abstract object like a triangle. What is it about the concrete world that allows application of the model? What is it about the world itself that accommodates the rationalist impulse to know why the world must be the way it is? The answer to these questions, and part of the thesis of this chapter, is that substance is thought by rationalists to ground the sub specie model and to secure the necessity they perceive in the world.

Substance