1 Russell and the Metaphysics of Neutral Monism John Hamilton 2 Summary of thesis (Abstract) My overall aim in this thesis is to elucidate the precise nature of Russell's mature 'neutral monist' metaphysic. I show how an understanding of it has been hampered by pervasive misunderstandings. The approach I take is an historical one, and my account reveals that, after his adoption of neutral monism in 1918, there were no radical changes in his worldview, and certainly no lurch from a supposed quasi-phenomenalistic system prior to 1921, to a causal theory of perception after 1927. Instead, the earlier system is not as phenomenalistic as is sometimes supposed and his later philosophy is a development, not a repudiation, of the themes in the earlier. Russell sought to show how his metaphysic dovetails with the outcome of modern physics in his 1927 book The Analysis of Matter. I seek to show how a proper understanding of modern physics indeed leads to Russellian conclusions. I also discuss the implications of quantum mechanics for metaphysics – a task which Russell could not have performed when he wrote The Analysis of Matter, since QM was still very much in a state of flux. I show how Russell moved from empiricism to a naturalistic position in the theory of knowledge, and in doing so supplied a definitive solution to Hume's scepticism. Once again, the usual perception of him as an “empiricist” fails to do justice to the complexity and subtlety of his philosophy. Finally, I argue that Russell's solution to the mind-body problem is the only one with any chance whatsoever of being true. In all this I seek to show how Russell's philosophy has been unjustly neglected in contemporary debates and how it can provide elegant solutions to contemporary philosophical puzzles in the philosophy of science, epistemology and the mind-body problem. 3 Contents Acknowledgements 4 Preface 5 Introduction 7 1. Russell’s Mature View of the World 10 2. The ‘Problem of Matter’ 18 3. Russell and Phenomenalism 34 4. The Continuity of Russell’s Philosophy 47 5. Russell, Newman and the Structural Realism Controversy 60 6. Philosophy and the Development of Twentieth Century Physics 78 7. The Russellian Approach to Intentionality 110 8. Theory of Knowledge: The Transformation of Empiricism 123 Conclusion: the ‘Mental’ and the ‘Physical’ 155 Appendix: Causality and the Quantum 159 Bibliography 165 4 Acknowledgements Firstly, I would like to thank the staff of the department of English, Communication and Philosophy at Cardiff University, particularly Rhian Rattray and Alison Venables. I would like to record here my very great gratitude to Dr Richard Gray, my thesis supervisor, for his inexhaustible patience and for his kind words of encouragement, as well as for his numerous useful suggestions and criticisms. I hope the result justifies his faith. I am also grateful to Alessandra Tanesini for providing me with invaluable assistance throughout my time at the department. I am indebted more than words can express to my good friend Professor Christopher Norris, quite possibly the wisest and most lovable man in the universe, as well as to all the wonderful postgraduate students at Cardiff University who participated in the Postgraduate Reading Group and from whom I derived much intellectual stimulation. I would like to thank Andrew Edgar for being Andrew Edgar. I am aware that he is not himself responsible for the law of identity, but I cannot help feeling that the world is better for this particular instance of it. Finally, I am grateful to Cardiff University for securing me the funding from the Arts and Humanities Research Council, without which I could not have completed my thesis. I depart from Cardiff University with many warm remembrances of the people I have come to know from being part of this academic community. Already my memories are acquiring the sepia sheen of nostalgia, regret and melancholy for that which must be irretrievably lost. 5 Preface The aim of this thesis is to expound and defend Russell's 'neutral monist' metaphysic. In particular, it is my contention that this metaphysic in large part supplies the correct solution to the 'mind-body problem'. Consequently, in the first four chapters I shall be attempting to explain the precise nature of Russell’s neutral monism and how it solved the problem of the relation of conscious states to brain processes. Russell’s solution to the mind-body problem has hitherto been largely obscured by pervasive and persistent misunderstandings concerning the nature of his metaphysic. These misunderstandings have, in turn, been fostered by misunderstandings concerning the course of Russell's philosophical development. This volume aims to put right this state of affairs. In the last four chapters of my thesis I shall be developing and extending the central ideas of Russell's metaphysic into other areas, specifically, the philosophy of science, the interpretation of physics, the philosophy of mind, and epistemology. I shall show how Russell's metaphysical framework and overall philosophical approach is capable of providing solutions to age-old problems in each of these areas, such as the problem of the nature of intentionality, and the 'problem of induction'. In each case, the solution to these problems was at least partially developed by Russell himself, though in each instance his ideas were not as fully developed as they were in the case of the mind-body problem. Thus the second portion of my thesis will be more speculative in nature than the first half. I shall begin this second part of my thesis by examining Newman's criticism of Russell's alleged 'structuralist' philosophy of science, and evaluating the extent to which his criticism need undermine a Russellian account. I shall argue that Russell's metaphysic is entirely capable of answering Newman, though not quite in the way Russell himself supposed. Furthermore, the correct solution to this puzzle throws further light on the fundamental and inescapable limits of our knowledge. I shall then examine how a Russellian metaphysic can successfully integrate and interpret the findings of modern natural science. I shall argue that relativity can be easily assimilated; indeed that, properly understood, it must lead to an account similar to that of Russell's. In the case of quantum mechanics I shall argue that current understandings of quantum mechanics are philosophically muddled and that a perfectly straightforward realist interpretation of quantum mechanics is available which is wholly consistent with Russell's scientific realism. Furthermore, I argue that this realist interpretation is precisely the one we ought to adopt on other grounds, simply from a careful examination of 6 quantum theory itself. I should mention here that I entirely reject the currently fashionable 'relative state', 'Many Worlds' and 'Many Minds' interpretations, for reasons which I hope shall become clear in the course of presenting my account. And whilst I have a considerable respect for the theories of Bohm, my account does not presuppose their validity. Moving on to the philosophy of mind, I argue that the same general approach that Russell applied to conscious states can also be profitably applied to the topic of intentional states, thus yielding a complete theory of mind. Lastly, I shall show that Russell's approach to the theory of knowledge in his mature system was less straightforwardly 'empiricist' than is customarily supposed, despite Russell's own professed allegiance to the empiricist tradition, and that his metaphysic is consistent with a naturalistic approach which indeed has a lot more in common with Kant than Russell himself was prepared to admit. In going beyond traditional empiricism, I argue that Russell supplied a wholly original approach to the problem of knowledge, one which throws fresh light on the traditional problems of epistemology and offers a route to definitive solutions in this field, just as his metaphysic offers a definitive solution to the mind-body problem. In particular, I maintain that the analysis of knowledge in Human Knowledge: Its Scope and Limits provides a philosophically satisfactory answer to Hume's scepticism in a manner that previous philosophical systems had largely failed to achieve. The empiricist answer to Hume in the twentieth century (for example in the works of A. J. Ayer) was simply to say that induction is the final court of appeal in evaluating factual inference, and is thus not itself susceptible to criticism in the light of any higher criterion. Whilst this may be correct, it cannot help but feel like something of an evasion. I think that Russell supplies something better, and far more sophisticated, an account which answers Hume in a manner that is not only completely definitive but is also wholly satisfying in a manner in which the ordinary empiricist answer to Hume is not. In the course of expounding his approach I also outline aspects of Russell's epistemology that have been largely ignored in the secondary literature, such as his strident rejection of 'induction' as a valid form of non-demonstrative inference, and his complete anticipation, by nearly twenty years, of Goodman's 'New Riddle of Induction'. Finally, in the conclusion to my thesis, I shall briefly return to the question of the mind-body problem, and argue that the Russellian solution to this problem is the only solution with any probability whatsoever of being true. 7 Introduction QUESTIONS It is a curious fact that, despite the considerable material that has been written about Russell, understanding of his mature metaphysic is somewhat sketchy. What, precisely, was Russell’s final view of the world? What relation does his final view bear towards his earlier views? Was there a radical change in his metaphysic involving his abandonment of phenomenalism and the adoption of a causal theory of perception alongside a scientific realism – a change concerning which he was strangely silent? Part of the reason that the answers to these questions have remained unclear is, I think, to be found in a seeming lack of interest in what the answers might be.