Materialism: A Philosophical Inquiry by Robin Gordon Brown and James Ladyman presents an introduction to the history and philosophy of materialism for non-specialists. The book revises the definition of ‘materialism’ based on lessons learned from breakthroughs in twentieth-century physics and offers an updated version of the old theory ‘physicalism’. This new approach is largely achieved without abandoning its introductory, pedagogical style, though there are a few occasions where the book may prove challenging even to philosophers who are well versed in the literature.
For some time now, a group of progressive philosophers (French and Ladyman ; Ladyman and Ross ; French ) have endeavoured to reconceptualize metaphysics in light of relativity and quantum physics. The significance of this enterprise has remained sadly neglected by the wider philosophical community, given that a limited number of philosophers are well versed in mathematical physics and set/model theory. The time for presenting a popular version of the new naturalist metaphysics is ripe and Brown and Ladyman’s book fills this need. What is more, the book engages with some important theories in the philosophy of mind in the context of these advances in physics and the reconceptualized metaphysics they spurred. As the authors rightly note, philosophers of mind have neglected how the advent of modern physics changed the scientific conception of matter, and this neglect has hindered their ability to engage with questions about the nature of mind and its relation with the world. Brown and Ladyman endeavour to demonstrate how this revised account of physicalism could shed light on staunch debates about the nature of mind and its relationship with the world. It is indeed fortunate that Materialism discusses this difficult, intriguing topic with enough clarity for a wide range of audiences.
The book is structured neatly into two parts: the first part recounts the historical development of materialism; the second part provides a more philosophical engagement with physicalism in the context of twentieth-century science and philosophy.
The first part, consisting of four chapters, provides a selective overview of the history of materialism from the first millennium BCE to nineteenth-century CE. Chapter 1 lays out the basic concepts of materialism, against the background of both rival and kindred views. Materialism is defined as the claim that ‘reality consists of material things and things that are wholly dependent for their existence on material things’ (p. 9). The chapter also contains a statement of the authors’ commitment to naturalism by remarking that their approach ‘claims no path to knowledge other than through scientific endeavour’ (p. 9). Chapter 2 traces the roots of materialism in ancient civilizations, such as India (with reference to the Carvaka tradition), and Ancient Greece (with reference to atomism and Epicureanism, among others). Brown and Ladyman identify the spread of Christianity as the cause of the demise of materialism in its early history. Chapter 3 brings the story into somewhat more recent times, turning to scientists such as Boyle and Newton, and philosophers such as Hobbes, Spinoza, and Hume, in the context of religious feuds and reformation. The chapter tells the story of the growth and dominance of materialism, which resulted in the liberation of scientific research from the yoke of dogma and authority.
Chapter 4 considers the rise of materialism in the context of the remarkable scientific and technological progress of the nineteenth century, and the victory of materialists such as Feuerbach and Marx over the idealism of Kant and Hegel. It also extols the role of Darwin’s theory of evolution in securing the dominance of materialism in the contemporary area. In all, despite being stated in general terms, the message of the first part of the book is clear: Brown and Ladyman argue that from ancient times until its zenith in the radical enlightenment, materialism had been the metaphysical centrepiece of intellectual history. Materialism embodied values of tolerance and free thinking, and created space for the rise of scientific thinking.
In the second part of the book—Chapters 5, 6, and 7—things change rather dramatically. Although this part also claims to be introductory, it engages with some of the most complex and intriguing issues in modern physics and philosophy of physics.
Chapter 5 moves into the twentieth century, where the kinetic theory of gases, as well as the progress of molecular biology, demonstrated how productive materialism could be. However, these advances were not sufficient to halt the demise, or at least the decline, of traditional materialism during this period. Surprisingly enough, given its history, this relegation of materialism was not at the hands of philosophical idealists or religious zealots, but rather resulted from developments within the field most cherished by materialists—physics. The emergence of general relativity and quantum theory loosened the grip of philosophers on the notion of matter. This is because relativity and many-particles physics proliferated a new theoretical vocabulary that could not be conceived of in terms of the traditional conception of matter and its properties. Individual objects and atoms were replaced by such things as ‘fields’ that do not map onto the orthodox, familiar metaphysics of everyday life. Similar progressive insights have been expressed previously in technical works (Ladyman and Ross ; French ), but Materialism makes them available to the general audience.
Chapter 6 sheds light on some controversial discussions in the philosophy of mind, informed by this scientific conception of physicalism. The important question here is about the relation between the mental and the physical. Could the former be reduced to the latter or identified with it (Smart ; Kim )? Philosophy of mind cannot provide the correct answer because it usually presupposes an outdated conception of ‘physical’ inherited from classical materialism, neglecting developments in contemporary theoretical physics. In this vein, after going out of their way to discuss the identity theory in detail (pp. 97–105), they remark, ‘What the identity theorists fail to take on board is just how profoundly science has abandoned traditional materialism’ (p. 104). It is one of the greatest contributions of Materialism that it embarks on characterizing and addressing the problem of the relationship between the mental and the physical in light of a scientifically informed conception of the physical.
There are also points in the book that could have been handled with more delicacy. For example, Brown and Ladyman occasionally make their own unsubstantiated, incautious claims about the ontological status of mental entities, when they submit that science does indeed acknowledge the existence of things such as atoms and molecules, ‘but no more than thoughts and feelings’ (p. 104). If the phrase is supposed to indicate that the existence of thoughts and feelings is a philosophically or scientifically established fact, this is wrong. The existential status of thoughts and feelings is less than fully clear in the science of mind, and they should not be presupposed by a scientific ontology any more than the existence of everyday entities would be presupposed by Ladyman and Brown (Beni and Northoff ). (They cannot presuppose the existence of ordinary objects, because the scientific image of the world does not necessarily include those objects.)
Chapter 6 also discusses the problem of mental causation, namely, if we accept the supervenience thesis (no change at the mental level without change at the physical level), we cannot explain how one mental event could cause another (without overdetermination by a physical event). But the authors do not explain how their version of physicalism could tackle this problem. They only ensure that physicalism can include mental entities in its ontology, given that physicalism designates everything (from mental events to sub-particle entities) as existent, despite presuming that they supervene on a to-be-discovered fundamental level of reality (p. 119). It could be argued (and indeed has been argued; see Crane and Mellor ; Crane ) that basing a definition of physicalism on what future physics may reveal about what is physical makes the doctrine a vacuous one, insofar as it can’t then include any specific commitments to the existence of any specific kind of entity, and allows for the inclusion of even mental entities into the physicalist ontology, provided that future physics could hypothesize the existence of those entities.
Moreover, while Brown and Ladyman claim to recognize the autonomy of action and agency, they trace the roots of desire and motive for action to a sub-mental level. But how can the autonomy of agency be reconciled to the reduction of agency to sub-mental mechanisms and processes? This is a hard problem, and Brown and Ladyman’s engagement with identity theory and supervenience physicalism is too sketchy (and a bit muddled) to ground a viable answer.
Chapter 7 spells out physicalism and clarifies its epistemological and ontological commitments. It specifies physicalism as a refutable form of materialism that is modified in light of the physics of the twentieth century. The modification here consists in shrinking the presumptuousness of traditional materialism by refraining from either epistemological or ontological claims about the nature or existence of the fundamental level of reality. This stance borders on some form of agnosticism about there being something that merits a label of ‘fundamental level’ (Schaffer ; Hüttemann ) that, while broad-minded, is incompatible with Brown and Ladyman’s promissory note in Chapter 6 (according to which, the problem of mental causation will be dissolved thanks to a future understanding of the fundamental level of physical reality). Brown and Ladyman’s statement of their perspective (or lack thereof) on ontological and epistemological components of physicalism here is a bit too truncated, and it’s not clear how far they want to go in stripping away ontological commitments of physicalism
Another instance of apparent inconsistency between the various statements of physicalism in Chapters 6 and 7 is to be found in the passing remark that physicalism would be refutable ‘if physics were to hypothesise an entity with demonstrably psychological properties in order to account for psychological Phenomena’ (p. 123). However, at least according to a naturalist approach, an entity that has its existence hypothesized by physics would be a physical entity, and its properties would be regarded as physical rather than psychological. This point was also made by Brown and Ladyman in Chapter 6: ‘The materialist designates all phenomena, from quarks to thoughts, as things that exist but which are supervenient on some more, yet-to-be-discovered, fundamental level of reality’ (p. 119). But the yet-to-be-discovered fundamental level of reality may include entities with demonstrably psychological properties. There is no a priori way (for a naturalist) to ensure that the fundamental level of reality as discovered by future physics won’t include entities with psychological properties. On the other hand, it defies Brown and Ladyman’s naturalist tendencies to assume that we will not adopt into the successful theories of future physics those entities that we currently consider to have psychological properties.
Chapter 8 is the conclusion of the book, and it seeks to determine the place of the physicalism within modern society.
Let us recap. Materialism is a clearly written, entertaining, and enlightening book that convincingly champions the cause of a tolerant form of physicalism. Despite being an introductory book, at times it engages in detail with some abstruse philosophical problems. The engagement with the identity theory and supervenience physicalism in the philosophy of mind is one of the more intriguing aspects of the book, for which it deserves praise. At the same time, the book opens the proverbial Pandora’s Box. To use a better metaphor, the book furrows the field and unearths the roots of several tangled problems that remain unsolved by the authors. The value of Brown and Ladyman’s work consists in showing what the roots of the problems are, rather than untangling or dissolving them. Hopefully, these problems will be discussed and untangled by these authors or others in due course.
Hüttemann, A. : What’s Wrong with Microphysicalism? London: Routledge.
Kim, J. : ‘Mental Causation and Consciousness: The Two Mind-Body Problems for the Physicalist’, in C. Gillett and B. Loewer (eds), Physicalism and Its Discontents, Cambridge: Cambridge University Press, pp. 271–83.