A review of recent work on physicalism, focusing on what it means to say nothing exists over and above the physical, how "the physical" should be defined, and the causal argument for physicalism.

The Exclusion Argument has afflicted non-reductionists for decades. In this article, I attempt to show that emergentism—the view that mental entities can downwardly cause physical entities in a non-overdetermining way—is the most plausible approach to solving the exclusion problem. The emergentist approach is largely absent in contemporary philosophy of mind, because emergentism rejects the Causal Closure of Physics, a doctrine embraced by almost all physicalists. This article, however, challenges the consensus on causal closure and defends a physicalist version of emergentism. (...) On closer examination, I find that neither physical evidence nor physicalist considerations can satisfactorily support causal closure. Moreover, I argue that two competing approaches that accept causal closure, compatibilism and autonomism, involve ad hoc postulations of mental causation. Therefore, all things considered, emergentism is the best option available to non-reductive physicalists. (shrink)

It is widely accepted that supervenience is a minimal commitment of physicalism. In this article, however, I aim to argue that physicalism should be exempted from the supervenience requirement. My arguments rely on a parallel between ontological dependence and causal dependence. Since causal dependence does not require causal determination, ontological dependence should not require ontological determination either. Moreover, my approach has a significant theoretical advantage: if physicalism is not committed to supervenience, then the metaphysical possibility of zombies—which is still wide (...) open after all these years—would pose no challenge to physicalism. (shrink)

Although physicalism is a dominant position in contemporary philosophy of mind and metaphysics, there are surprisingly very few serious arguments for physicalism, which may contribute to the revival of anti-physicalism in recent decades. In this article, I develop a causal argument for physicalism in general, inspired by the causal argument for reductive physicalism. By comparing each pair of premises, I argue that, while the causal argument for reductive physicalism is controversial, the causal argument for physicalism simpliciter is promising.

A popular response to the Exclusion Argument for physicalism maintains that mental events depend on their physical bases in such a way that the causation of a physical effect by a mental event and its physical base needn’t generate any problematic form of causal overdetermination, even if mental events are numerically distinct from and irreducible to their physical bases. This paper presents and defends a form of dualism that implements this response by using a dispositional essentialist view of properties to (...) argue that the psychophysical laws linking mental events to their physical bases are metaphysically necessary. I show the advantages of such a position over an alternative form of dualism that merely places more “modal weight” on psychophysical laws than on physical laws. The position is then defended against the objection that it is inconsistent with dualism. Lastly, some suggestions are made as to how dualists might clarify the contribution that mental causes make to their physical effects. (shrink)

Recent years have seen renewed interest in the emergence issue. The contemporary debate, in contrast with that of past times, has to do not so much with the mind–body problem as with the relationship between the physical and other domains; mostly with the biological domain. One of the main sources of this renewed interest is the study of complex and, in general, far-from-equilibrium self-preserving systems, which seem to fulfil one of the necessary conditions for an entity to be emergent; namely, (...) that its causal powers are not predictable from the causal powers of basic physical properties. However, I argue that much of the current emergentism debate has misfired by focusing on the interpretation of self-maintaining systems. In contrast, I claim that if we want to find emergent properties, we should look not at complex systems, but at selection (natural selection, in particular). I argue that selection processes make the causal world ‘exuberant’ by making non-physical functional and relational properties enter the causal web of the world. (shrink)

As a first pass, physicalism is the doctrine that there is nothing over and above the physical. Much recent philosophical work has been devoted to spelling out what this means in more rigorous terms and to assessing the case for the view. What follows is a survey of such work. I begin by looking at competing accounts of what is meant by nothing over and above and then turn to how the physical should be understood. Once we are clear on (...) the options for formulating the physicalist thesis, we will look at the leading argument for the view. Along the way, I will suggest avenues for further exploration. (shrink)

Dualism holds that some mental events are fundamental and non-physical. I develop a prima facie plausible causal argument for dualism. The argument has several significant implications. First, it constitutes a new way of arguing for dualism. Second, it provides dualists with a parity response to causal arguments for physicalism. Third, it transforms the dialectical role of epiphenomenalism. Fourth, it refutes the view that causal considerations prima facie support physicalism but not dualism. After developing the causal argument for dualism and drawing (...) out these implications, I subject the argument to a battery of objections. Some prompt revisions to the argument. Others reveal limitations in scope. It falls out of the discussion that the causal argument for dualism is best used against physicalism as a keystone in a divide and conquer strategy. (shrink)

The chief motivation for epiphenomenalist dualism is its promise to solve dualism’s causal exclusion problem without inducing causal overdetermination or violations of the causal closure of the physical. This paper argues that epiphenomenalist dualism is itself susceptible to an exclusion problem. The problem exploits symmetries of determination and influence generated by a wide class of physical theories. Further, I argue that there is an interference effect between solving epiphenomenalist dualism's exclusion problem and using epiphenomenalist dualism as a solution to the (...) causal exclusion problem. What emerges is an overlooked, empirically-motivated challenge to epiphenomenalist dualism. (shrink)

The conservation of energy and momentum have been viewed as undermining Cartesian mental causation since the 1690s. Modern discussions of the topic tend to use mid-nineteenth century physics, neglecting both locality and Noether’s theorem and its converse. The relevance of General Relativity has rarely been considered. But a few authors have proposed that the non-localizability of gravitational energy and consequent lack of physically meaningful local conservation laws answers the conservation objection to mental causation: conservation already fails in GR, so there (...) is nothing for minds to violate. This paper is motivated by two ideas. First, one might take seriously the fact that GR formally has an infinity of rigid symmetries of the action and hence, by Noether’s first theorem, an infinity of conserved energies-momenta. Second, Sean Carroll has asked how one should modify the Dirac–Maxwell–Einstein equations to describe mental causation. This paper uses the generalized Bianchi identities to show that General Relativity tends to exclude, not facilitate, such Cartesian mental causation. In the simplest case, Cartesian mental influence must be spatio-temporally constant, and hence 0. The difficulty may diminish for more complicated models. Its persuasiveness is also affected by larger world-view considerations. The new general relativistic objection provides some support for realism about gravitational energy-momentum in GR. Such realism also might help to answer an objection to theories of causation involving conserved quantities, because energies-momenta would be conserved even in GR. (shrink)

Since Leibniz's time, Cartesian mental causation has been criticized for violating the conservation of energy and momentum. Many dualist responses clearly fail. But conservation laws have important neglected features generally undermining the objection. Conservation is _local_, holding first not for the universe, but for everywhere separately. The energy in any volume changes only due to what flows through the boundaries. Constant total energy holds if the global summing-up of local conservation laws converges; it probably doesn't in reality. Energy conservation holds (...) if there is symmetry, the sameness of the laws over time. Thus, if there are time-places where symmetries fail due to nonphysical influence, conservation laws fail there and then, while holding elsewhere, such as refrigerators and stars. Noether's converse first theorem shows that conservation laws imply symmetries. Thus conservation trivially nearly entails the causal closure of the physical. But expecting conservation to hold in the brain simply assumes the falsehood of Cartesianism. Hence Leibniz's objection begs the question. Empirical neuroscience is another matter. So is Einstein's General Relativity: far from providing a loophole, General Relativity makes mental causation _harder_. (shrink)

Misconceptions about energy conservation abound due to the gap between physics and secondary school chemistry. This paper surveys this difference and its relevance to the 1690s–2010s Leibnizian argument that mind-body interaction is impossible due to conservation laws. Justifications for energy conservation are partly empirical, such as Joule’s paddle wheel experiment, and partly theoretical, such as Lagrange’s statement in 1811 that energy is conserved if the potential energy does not depend on time. In 1918 Noether generalized results like Lagrange’s and proved (...) a converse: symmetries imply conservation laws and vice versa. Conservation holds if and only if nature is uniform. The rise of field physics during the 1860s–1920s implied that energy is located in particular places and conservation is primordially local: energy cannot disappear in Cambridge and reappear in Lincoln instantaneously or later; neither can it simply disappear in Cambridge or simply appear in Lincoln. A global conservation law can be inferred in some circumstances. Einstein’s General Relativity, which stimulated Noether’s work, is another source of difficulty for conservation laws. As is too rarely realized, the theory admits conserved quantities due to symmetries of the Lagrangian, like other theories. Indeed General Relativity has more symmetries and hence more conserved energies. An argument akin to Leibniz’s finally gets some force. While the mathematics is too advanced for secondary school, the ideas that conservation is tied to uniformities of nature and that energy is in particular places, are accessible. Improved science teaching would serve the truth and enhance the social credibility of science. (shrink)

In order to defend mental explanations dualists may appeal to dispositions (powers). By accepting a powers theory of causation, a dualist can more plausibly defend mental explanations that are given independently of physical explanations. Accepting a power-based theory still comes with a price. Absences and double preventers are not causes in a powers theory, and solutions based on them can only defend their explanatory relevance in mental explanations. There is still a chance that such mental explanations can be causal explanations, (...) though they do not refer to real causes. (shrink)

The aim of the present paper is twofold. First, we are interested in assessing the validity of one version of Kim’s argument against genuine higher level causation. Second, we discuss Wilson’s proposal to consider a weaker notion of emergence as genuinely metaphysical and compatible with Non-Reductive Physicalism. Our conclusion is that both proposals fail: the first in preempting genuine (strong) emergent causation, whereas the second in ensuring a genuinely metaphysical status to weak emergence. After all, Wilson’s proposal strongly depends on (...) the success of Kim’s, not only because it takes it as valid but, also, because in pursuing its own weaker model it shares the presuppositions that led Kim’s to failure. At the end of the day, Wilson’s conception of genuine weak emergence either breaks causal closure or is merely stipulative, namely confined at the descriptive level. (shrink)

The argument from causal closure of the physical is usually considered the most powerful argument in favor of the ontological doctrine of physicalism. Many authors, most notably Papineau, assume that CCP implies that physicalism is supported by physics. I demonstrate, however, that physical science has no bias in the ontological debate between proponents of physicalism and dualism. I show that the arguments offered for CCP are effective only against the accounts of mental causation based on the action of the mental (...) forces of a Newtonian nature, i.e. those which manifest themselves by causing accelerations. However, it is conceivable and possible that mental causation is manifested through the redistribution of energy, momentum and other conserved quantities in the system, brought about by altering the state probability distribution within the living system and leading to anomalous correlations of neural processes. After arguing that a probabilistic, interactionist model of mental causation is conceivable, which renders the argument from causal closure of the physical ineffective, I point to some basic features that such a model must have in order to be intelligible. At the same time, I indicate the way that conclusive testing of CCP can be done within the theoretical framework of physics. (shrink)

The argument from causal closure of the physical is usually considered the most powerful argument in favor of the ontological doctrine of physicalism. Many authors, most notably Papineau, assume that CCP implies that physicalism is supported by physics. I demonstrate, however, that physical science has no bias in the ontological debate between proponents of physicalism and dualism. I show that the arguments offered for CCP are effective only against the accounts of mental causation based on the action of the mental (...) forces of a Newtonian nature, i.e. those which manifest themselves by causing accelerations. However, it is conceivable and possible that mental causation is manifested through the redistribution of energy, momentum and other conserved quantities in the system, brought about by altering the state probability distribution within the living system and leading to anomalous correlations of neural processes. After arguing that a probabilistic, interactionist model of mental causation is conceivable, which renders the argument from causal closure of the physical ineffective, I point to some basic features that such a model must have in order to be intelligible. At the same time, I indicate the way that conclusive testing of CCP can be done within the theoretical framework of physics. (shrink)

We examine Sophie Gibb’s emergent property-dualist theory of mental causation as double-prevention. Her account builds on a commitment to a version of causal realism based on a powers metaphysic. We consider three objections to her account. We show, by drawing out the implications of the ontological commitments of Gibb’s theory of mental causation, that the first two objections fail. But, we argue, owing to worries about cases where there is no double-preventive role to be played by mental properties, her account, (...) which solely affords mental properties a double-preventive role, is incomplete and vulnerable to a causal exclusion objection. We propose a friendly modification to her theory of mental causation that is consistent with her theory’s ontological commitments. Specifically, we sketch an account on which mental properties have a more pronounced causal-structuring role that is not exhausted by the role Gibb assigns them as double-preventers. The result is a novel emergentist theory of mental causation. (shrink)

The idea that mind and body are distinct entities that interact is often claimed to be incompatible with physics. The aim of this paper is to disprove this claim. To this end, we construct a broad mathematical framework that describes theories with mind–body interaction (MBI) as an extension of current physical theories. We employ histories theory, i.e., a formulation of physical theories in which a physical system is described in terms of (i) a set of propositions about possible evolutions of (...) the system and (ii) a probability assignment to such propositions. The notion of dynamics is incorporated into the probability rule. As this formulation emphasises logical and probabilistic concepts, it is ontologically neutral. It can be used to describe mental ‘degrees of freedom’ in addition to physical ones. This results into a mathematical framework for psycho-physical interaction (ΨΦ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\Psi \Phi$$\end{document}I formalism). Interestingly, a class of ΨΦ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\Psi \Phi$$\end{document}I theories turns out to be compatible with energy conservation. (shrink)

The principle of energy conservation is widely taken to be a se- rious difficulty for interactionist dualism (whether property or sub- stance). Interactionists often have therefore tried to make it satisfy energy conservation. This paper examines several such attempts, especially including E. J. Lowe’s varying constants proposal, show- ing how they all miss their goal due to lack of engagement with the physico-mathematical roots of energy conservation physics: the first Noether theorem (that symmetries imply conservation laws), its converse (that conservation (...) laws imply symmetries), and the locality of continuum/field physics. Thus the “conditionality re- sponse”, which sees conservation as (bi)conditional upon symme- tries and simply accepts energy non-conservation as an aspect of interactionist dualism, is seen to be, perhaps surprisingly, the one most in accord with contemporary physics (apart from quantum mechanics) by not conflicting with mathematical theorems basic to physics. A decent objection to interactionism should be a posteri- ori, based on empirically studying the brain. (shrink)

The Exclusion Argument for physicalism maintains that since (1) every physical effect has a sufficient physical cause, and (2) cases of causal overdetermination are rare, it follows that if (3) mental events cause physical events as frequently as they seem to, then (4) mental events must be physical in nature. In defence of (1), it is sometimes said that (1) is supported if not entailed by conservation laws. Against this, I argue that conservation laws do not lend sufficient support to (...) (1) to render its denial ‘unscientific’, and that those who accept (3) and deny (4) may consequently respond to the Exclusion Argument by denying (1) without thereby setting themselves at odds with current science. I also argue that conservation laws are compatible with (3) and the negation of (4), and that one can therefore accept conservation laws and (3) while denying both (1) and (4). (shrink)

Interactive dualism is notorious for supporting genuine and autonomous mental causation that is allegedly impossible for its confliction with basic principles of physics. The purpose of this essay is to show the invalidity of this commonplace view, by arguing to the contrary in three different steps. First, I will deal with the objection about the non-scientific character of interactive dualism, as it is conceived of in present-day philosophy of mind. Second, I will illustrate and critically examine three contemporary models of (...) dualistically understood mental causation. Finally, I will summarise the chief assumptions made in these models and try to lay down my own proposal. (shrink)

I defend a dualist model of psychophysical causal relevance, according to which mental events are not causes in the physical domain, but are causally relevant in this domain because they enable — or, in other words, provide the appropriate structure for — physical events to be caused. More specifically, I defend the claim that mental events are ‘double preventers’ within the physical domain, where double preventers are a type of enabling event. The distinction that I make between causes and enabling (...) events and the dualist model of psychophysical causal relevance that I defend has emerged from my acceptance of the powers theory of causation. In this paper, I explore how this dualist model of psychophysical causal relevance offers a response to Papineau’s defence of the causal completeness principle via the conservation laws. (shrink)