The previous decade has seen renewed critical interest in the multiple realization argument. These criticisms constitute a "second wave" of challenges to this central argument in late-20th century philosophy of mind. Unlike the first wave, which challenged the premise that multiple realization is inconsistent with reduction or type identity, this second wave challenges the truth of the multiple realization premise itself. Since psychoneural reductionism was prominent among the explicit targets of the multiple realization argument, one might (...) think that this second wave of challenges provides important aid and comfort to reductionists. In this paper, however, I provide reasons for thinking it does not. This is not to the detriment of psychoneural reductionism because, as I also argue here, and unrecognized by the current non-reductive orthodoxy in philosophy of mind, one key argument among the first wave of criticisms of the multiple realization argument has never been adequately rejoined. (shrink)

Issues of identity and reduction have monopolized much of the philosopher of mind’s time over the past several decades. Interestingly, while investigations of these topics have proceeded at a steady rate, the motivations for doing so have shifted. When the early identity theorists, e.g. U. T. Place ( 1956 ), Herbert Feigl ( 1958 ), and J. J. C. Smart ( 1959 , 1961 ), fi rst gave voice to the idea that mental events might be identical to brain processes, (...) they had as their intended foil the view that minds are immaterial substances. But very few philosophers of mind today take this proposal seriously. Why, then, the continued interest in identity and reduction? Th e concern, as philosophers like Hilary Putnam and Jerry Fodor have expressed it, is that a victory for identity or reduction is a defeat for psychology. For if minds are physical, or if mental events are physical events, then psychologists might as well disassemble their laboratories, making room for the neuroscientists and molecular biologists who are in a better position to explain those phenomena once misdescribed as “psychological.” Th e worry nowadays is not that locating thought in immaterial souls will make psychology intractable, but that locating thoughts in material brains will make it otiose. (shrink)

Many empirically minded philosophers have used neuroscientific data to argue against the multiple realization of cognitive functions in existing biological organisms. I argue that neuroscientists themselves have proposed a biologically based concept of multiple realization as an alternative to interpreting empirical findings in terms of one‐to‐one structure‐function mappings. I introduce this concept and its associated research framework and also how some of the main neuroscience‐based arguments against multiple realization go wrong. *Received October 2009; revised December 2009. †To (...) contact the author, please write to: Department of Philosophy, 260 English‐Philosophy Building, University of Iowa, Iowa City, IA 52242; e‐mail: carrie‐[email protected]. (shrink)

Biologists seems to hold two fundamental beliefs: Organisms are organized into levels and the individuals at these levels differ in their properties. Together these suggest that there will be massive multiple realization, i.e. that many human psychological properties are multiply realized at many neurobiological levels. This paper provides some documentation in support of this suggestion.

Opponents to consciousness in fish argue that fish do not feel pain because they do not have a neocortex, which is a necessary condition for feeling pain. A common counter-argument appeals to the multiple realizability of pain: while a neocortex might be necessary for feeling pain in humans, pain might be realized differently in fish. This paper argues, first, that it is impossible to find a criterion allowing us to demarcate between plausible and implausible cases of multiple realization (...) of pain without running into a circular argument. Second, opponents to consciousness in fish cannot be provided with reasons to believe in the multiple realizability of pain. I conclude that the debate on the existence of pain in fish is impossible to settle by relying on the multiple realization argument. (shrink)

Polger and Shapiro argue that their official recipe, a criterion for judging when the phenomenon of multiple realization exists, renders MR less widespread than its proponents have assumed. I argue that, although Polger and Shapiro’s criterion is a useful contribution, they arrive at their conclusion too hastily. Contrary to Polger and Shapiro, I claim that the phenomenon of multiple realization in the biological world, judged by their criterion, is not as scarce as they suggest. To show this, an (...) updated official recipe, namely a multiple mechanistic realization thesis, integrating Polger and Shapiro’s criterion with a compositional conception of realization, is developed. Then, three examples of varied kinds are examined, showing that cases of MR are not so hard to find in the biological world. (shrink)

Forthcoming in Philosophy of Science. Despite some recent advances, multiple realization remains a largely misunderstood thesis. Consider the dispute between Lawrence Shapiro and Carl Gillett over the application of Shapiro’s recipe for deciding when we have genuine cases of multiple realization. I argue that Gillett follows many philosophers in mistakenly supposing that multiple realization is absolute and transitive. Both of these are problematic. They are tempting only when we extract the question of multiple realization from the (...) explanatory context in which it is invoked. Anchoring multiple realizability in its theoretical context provides grounds for arbitrating disagreements. Doing so, I argue, favors the view advanced by Shapiro. (shrink)

This paper explores the relationship between psychology and neurobiology in the context of cognitive science. Are the sciences that constitute cognitive science independent and theoretically autonomous, or is there a necessary interaction between them? I explore Fodor's Multiple Realization Thesis (MRT) which starts with the fact of multiple realization and purports to derive the theoretical autonomy of special sciences (such as psychology) from structural sciences (such as neurobiology). After laying out the MRT, it is shown that, on closer (...) inspection, the argument is either circular or self-undermining--the argument either assumes the very autonomy it seeks to demonstrate or the concluded autonomy is contradicted by the theoretical interdependence invoked by the premises of the argument. Next, I explore a concrete example of multiple realization in the explanation of animal behavior: the convergent evolution of jamming avoidance behaviors in three genera of weakly electric fish. Contrary to the image painted by the MRT, the work on these animals involves a high degree of interaction between the various levels of investigation. The fact that our understanding of electric fish behavior involves functional theories and multiple realization without the kind of disunified science that is supposed to follow from such a situation indicates that the mere fact of multiple realization cannot be the basis for an autonomous psychology. (shrink)

Despite the remarkable advances in behavioral and brain sciences over the last decades, the mind/body (brain) problem is still an open debate and one of the most intriguing questions for both cognitive neuroscience and philosophy of mind. Traditional approaches have conceived this problem in terms of a contrast between physicalist monism and Cartesian dualism. However, since the late sixties, the landscape of philosophical views on the problem has become more varied and complex. The Multiple Realization Thesis (MRT) claims that (...) mental properties can be (or are) realized, and mental processes can be (or are) implemented by neural correlates of different kinds. Thus, MRT challenges the psychoneural type-identity theory and the corresponding reductionism. Many philosophers have acknowledged the a priori plausibility of MRT. However, the existence of empirical evidence in favor of intraspecific, human multiple realizations of mental processes and properties is still controversial. Here we illustrate some cases that provide empirical evidence in support of MRT. Recently, it has been proposed that foveal agnosic vision, like peripheral vision, can be restored by increasing object parts’ spacing (Strappini et al., 2017a; Crutch and Warrington, 2007). Agnosic fovea and normal periphery are both limited by crowding, that impairs object recognition, and provides the signature of visual integration. Here we define a psychological property of restored object identification and we cross-reference the data of visually-impaired patients with different etiologies. In particular, we compare the data of two stroke patients, two patients with posterior cortical atrophy (PCA), six cases of strabismic amblyopia, and one case with restored sight. We also compare these patients with unimpaired subjects tested in the periphery. We show that integration (i.e. restored recognition) seems to describe quite accurately the visual performance in all these cases. While the patients have different etiologies and different neural correlates, the unimpaired subjects have no neural damage. Thus similarity in the psychological property given the differences in the neural substrate can be interpreted in relation to MRT and provide evidence in its support. Finally, we will frame our contribution within the current debate concerning MRT providing new and compelling empirical evidence. (shrink)

The argument from multiple realization is currently considered the argument against intertheoretic reduction. Both Little and Kincaid have applied the argument to the individualism-holism debate in support of the antireductionist holist position. The author shows that the tenability of the argument, as applied to the individualism-holism debate, hinges on the descriptive constraints imposed on the individualist position. On a plausible formulation of the individualist position, the argument does not establish that the intertheoretic reduction of social theories is highly unlikely. (...) Nonetheless, the reductive project may run into other potential obstacles. For this reason, it is concluded that the prospect of intertheoretic reduction is uncertain rather than unlikely. Key Words: argument from multiple realization • intertheoretic reduction • reductionism • individualism • holism. (shrink)

According to the multiple realization argument, mental states or processes can be realized in diverse and heterogeneous physical systems; and that fact implies that mental state or process kinds cannot be identified with particular kinds of physical states or processes. More specifically, mental processes cannot be identified with brain processes. Moreover, the argument provides a general model for the autonomy of the special sciences. The multiple realization argument is widely influential, but over the last thirty years it has (...) also faced serious objections. Despite those objections, most philosophers regard the fact of multiple realization and the cogency of the multiple realization argument as plainly correct. Why is that? What is it about the multiple realization argument that makes it so resilient? One reason is that the multiple realization argument is deeply intertwined with a view that minds are, in some sense, computational. But we argue that the sense in which minds are computational does not support the conclusion that they are ipso facto multiply realized. We argue that the sense in which brains compute does not imply that brains implement multiply realizable computational processes, and it does not provide a general model for the autonomy of the special sciences. (shrink)

This paper has two principal goals. The first is to set out a bit of conceptual cartography, mapping out a number of distinct conceptual issues that are frequently conflated in the vast literature on multiple realization. The second is to review very briefly how work by Carl Gillett and myself attempts to address a few of the many problems of multiple realization. One of these is explaining what Jerry Fodor apparently took to be mysterious, namely, how multiple (...) realization of properties is possible. (shrink)

Abstract:Polger and Shapiro have two principal takes on realization: An individual being a member of a kind is an instance of realization, and a kind being a member of a kind is an instance of realization. Both of these conceptions of realization suffer from serious objections. The broader conclusion that emerges from these many flaws is that, while their versions of realization and multiple realization are implausible, this does nothing to undermine the viability of more recent versions of nonreductive (...) physicalism based on property instances. (shrink)

Biologists seems to hold two fundamental beliefs: Organisms are organized into levels and the individuals at these levels differ in their properties. Together these suggest that there will be massive multiple realization, i.e. that many human psychological properties are multiply realized at many neurobiological levels. This paper provides some documentation in support of this suggestion.

It is commonly believed that there is a fundamental incompatibility between multiple realization and type identity in the philosophy of mind. This claim can be challenged, however, since a single neural type may be realized by different microphysical types. In this case, the identity statement would connect the psychological and the neural type, while the neural type, in turn, could be multiply realized by different microphysical types. Such a multiple realization of higher level types occurs quite frequently even (...) within physics and it should be acceptable for physicalism in general. (shrink)

Multiple realisation prompts the question: how is it that multiple systems all exhibit the same phenomena despite their different underlying properties? In this paper I develop a framework for addressing that question and argue that multiple realisation can be reductively explained. I illustrate this position by applying the framework to a simple example – the multiple realisation of electrical conductivity. I defend my account by addressing potential objections:contra Polger and Shapiro, Batterman, and Sober, (...) I claim that multiple realisation is commonplace, that it can be reductively explained, but that it requires asui generisreductive explanatory strategy. (shrink)

This paper was written for and presented at a symposium on Multiple Realizability at the Central Division of the APA in 2022. It's in somewhat rough shape, especially the later parts. I hope to be in a position soon to post a revised and more carefully worked out version. The basic argument of the first half is this: Realization of the interesting sort (and thus MR of the interesting sort) requires tidy separation of levels (with realizers being at a (...) lower level than that which they realize). The success of mixed-scale, mixed-resource (i.e., multi-grain) modeling strongly suggests that such a tidy separation of levels is not in the cards. Thus, MR is (likely) not a widespread phenomenon in our universe. The second half of the paper develops a relation of "multiple explainability" that is meant to play the role, in many contexts, of MR, while being metaphysically and methodologically messier than MR. (shrink)

‘Epistemic structural realism’ (ESR) insists that all that we know of the world is its structure, and that the ‘nature’ of the underlying elements remains hidden. With structure represented via Ramsey sentences, the question arises as to how ‘hidden natures’ might also be represented. If the Ramsey sentence describes a class of realisers for the relevant theory, one way of answering this question is through the notion of multiple realisability. We explore this answer in the context of the work (...) of Carnap, Hintikka and Lewis. Both Carnap and Hintikka offer clear structuralist perspectives which, crucially, accommodate the openness inherent in theory change. Unfortunately there is little purchase for a viable form of realism in either case. Lewis’s approach, on the other hand, offers more scope for realism but, as we shall see, concerns arise as to whether a relevant form of structuralism can be maintained. In particular his thesis of Ramseyan humility undermines certain conceptions of scientific laws that the structural realist might naturally cleave to. Our overall conclusion is that the representational device of Ramsey sentence plus multiple realisability can accommodate either the structuralist or realist aspects of ESR but has difficulties capturing both. (shrink)

The thesis of multiple realisation that Borsboom et al. are relying on should not be taken for granted. In dissolving the apparent multiple realisation, the reductionist research strategies in psychopathology research (the Research Domain Criteria [RDoC] framework, in particular) are bound to lead to eliminativism rather than reductionism. Therefore, Borsboom et al. seem to be aiming at a wrong target.

The target of this article is the claim that natural selection accounts for the multiple realisation of biological and psychological kinds. I argue that the explanation actually offered does not provide any insight about the phenomenon since it presupposes multiple realisation as an unexplained premise, and this is what does all the work. The purported explanation mistakenly invokes the ?indifference? of selection to structure as an additional explanatorily relevant factor. While such indifference can be explanatory in (...) intentional contexts, it is not a causal factor at all in non-intentional nature. The upshot is that, once the necessary initial assumption about heterogeneity is accepted, there is no further explanation to do. (shrink)

Biochemical kinds such as proteins pose interesting problems for philosophers of science, as they can be studied from the points of view of both biology and chemistry. The relationship between the biological functions of biochemical kinds and the microstructures that they are related to is the key question. This leads us to a more general discussion about ontological reductionism, microstructuralism, and multiple realization at the biology-chemistry interface. On the face of it, biochemical kinds seem to pose a challenge for (...) ontological reductionism and hence motivate a dual theory of chemical and biological kinds, a type of pluralism about natural kinds. But it will be argued that the challenge, which is based on multiple realization, can be addressed. The upshot is that there are reasonable prospects for ontological reductionism about biochemical kinds, which corroborates natural kind monism. (shrink)

Thomas Polger and Laurence Shapiro argue that Carl Gillett's much publicized dimensioned theory of realization is incoherent, being subject to a reductio. Their argument turns on the fact that Gillett's definition of realization makes property instances the exclusive relata of the realization relation, while his belief in multiple realization implies its denial, namely, that properties are the relata of the realization relation on occasions of multiple realization. Others like Sydney Shoemaker have also expressed their view of realization in (...) terms of property instances, yet they too have accepted the multiple realizability of properties. Thus I am interested in the more general issue raised by Polger and Shapiro's argument. Specifically, I show how to supplement a theory of realization with a category-inclusive auxiliary assumption, which avoids the stated reductio. I then offer a few reasons to justify the proposed category-inclusive view of realization, making some comparisons to supervenience and causation along the way. (shrink)

In this paper, I defend an updated account of functional kinds, initially presented by Daniel Weiskopf, from the criticism that functional kinds will not qualify as scientific kinds. An important part of Weiskopf’s account is that functional kinds are multiply realisable. The criticisms I consider avoid discussion of multiple realisability. Instead, it is argued that functional kinds carry inferior counterfactual profiles when compared to other accounts of kinds. I respond to this charge by arguing that this criticism fails to (...) take into consideration the role that multiple realisability can play in providing important explanatory counterfactuals. I do so by highlighting some points made by Lauren Ross that highlight where multiple realisability is explanatorily pertinent. I then argue that the criticisms of Weiskopf’s account fail to establish the explanatory inferiority of functional kinds. (shrink)

Carl Gillett has defended what he calls the “dimensioned” view of the realization relation, which he contrasts with the traditional “flat” view of realization (2003, 2007; see also Gillett 2002). Intuitively, the dimensioned approach characterizes realization in terms of composition whereas the flat approach views realization in terms of occupiers of functional roles. Elsewhere we have argued that the general view of realization and multiple realization that Gillett advances is not able to discharge the theoretical duties of those relations (...) (Shapiro 2004, unpublished manuscript; Polger 2004, 2007, forthcoming). Here we focus on an internal objection to Gillett’s account and then raise some broader reasons to reject it. (shrink)

The article maintains that chronic fatigue syndrome can be properly understood only by taking an integrated perspective in which evolutionary, developmental and ecological aspects are considered. The integrative approach, supplemented by a complexity theory and psychoneuroimmunological research, is capable of explaining why there are so few structural aberrations to be found in chronic fatigue syndrome and why specific treatment is so difficult to establish. A major outcome of the investigation, that all individuals with chronic fatigue syndrome are diseased in their (...) own way, emphasises the need to study the development of personalised life histories. It also highlights an ethical dimension; personalised disease defies essentialist thinking on patient management. Another major outcome, which follows from the developmental systems perspective, is the dissolution of ontological mind-body dualism. This in turn allows for a methodological complementation of the biological and phenomenological approaches to knowledge. New research strategies that may help to resolve chronic fatigue syndrome, grounded in the revised perspective on individual development, are suggested. (shrink)

It is often thought that the computational paradigm provides a supporting case for the theoretical autonomy of the science of mind. However, I argue that computation is in fact incompatible with this alleged aspect of intentional explanation, and hence the foundational assumptions of orthodox cognitive science are mutually unstable. The most plausible way to relieve these foundational tensions is to relinquish the idea that the psychological level enjoys some special form of theoretical sovereignty. So, in contrast to well known antireductionist (...) views based on multiple realizability, I argue that the primary goal of a computational approach to the mind should be to facilitate a translation of the psychological to the neurophysiological. (shrink)

Several philosophers (e.g., Ehring (Nous (Detroit, Mich.) 30:461–480, 1996 ); Funkhouser (Nous (Detroit, Mich.) 40:548–569, 2006 ); Walter (Canadian Journal of Philosophy 37:217–244, 2007 ) have argued that there are metaphysical differences between the determinable-determinate relation and the realization relation between mental and physical properties. Others have challenged this claim (e.g., Wilson (Philosophical Studies, 2009 ). In this paper, I argue that there are indeed such differences and propose a “mechanistic” account of realization that elucidates why these differences hold. This (...) account of realization incorporates two distinct roles that mechanisms play in the realization of mental (and other special science) properties which are implicit, but undeveloped, in the literature—what I call “constitutive” and “integrative” mechanisms. I then use these two notions of mechanism to clarify some debates about the relations between realization, multiple realizability, and irreducibility. (shrink)

This paper discusses in broad terms the metaphysical projects of Sydney Shoemaker’s Physical Realization . Specifically, I examine the effectiveness of Shoemaker’s novel “subset” account of realization for defusing the problem of mental causation, and compare the “subset” account with the standard “second-order” account. Finally, I discuss the physicalist status of the metaphysical worldview presented in Shoemaker’s important new contribution to philosophy of mind and metaphysics.

Sydney Shoemaker has been arguing for more than a decade for an account of the mind–body problem in which the notion of realization takes centre stage. His aim is to provide a notion of realization that is consistent with the multiple realizability of mental properties or events, and which explains: how the physical grounds the mental; and why the causal work of mental events is not screened off by that of physical events. Shoemaker's proposal consists of individuating properties in (...) terms of causal powers, and defining realization as a relation of inclusion between sets of causal powers. Thus, as the causal powers that define a mental property are a subset of the causal powers that characterize a physical property, it can be said that physical properties realize mental properties. In this paper we examine the physicalist credentials of Shoemaker's mind–body theory in relation to three important issues: the direction of the relation of dependence that the theory is committed to; the possibility of mental properties existing without being anchored by physical properties; and the compatibility of the theory with the causal closure of the physical world. We argue that Shoemaker's theory is problematic in all three respects. After that we consider whether the theory should count as a mind–body theory at all, given that it seems to be committed to a distorted view of mental properties. (shrink)

This paper examines, for the first time, the relationship between realization relations and the free energy principle in cognitive neuroscience. I argue, firstly, that the free energy principle has ramifications for the wide versus narrow realization distinction: if the free energy principle is correct, then organismic realizers are insufficient for realizing free energy minimization. I argue, secondly, that the free energy principle has implications for synchronic realization relations, because free energy minimization is realized in dynamical agent-environment couplings embedded at (...) class='Hi'>multiple time scales. (shrink)

Christian List and Peter Menzies 2009 have looked to interventionist theories of causation for an answer to Jaegwon Kim's causal exclusion problem. Important to their response is the idea of realization-insensitivity. However, this idea becomes mired in issues concerning multiple realization, leaving it unable to fulfil its promise to block exclusion. After explaining why realization-insensitivity fails as a solution to Kim's problem, I look to interventionism to describe a different kind of solution.

It is commonly maintained that neuroplastic mechanisms in the brain provide empirical support for the hypothesis of multiple realizability. We show in various case studies that neuroplasticity stems from preexisting mechanisms and processes inherent in the neural structure of the brain. We argue that not only does neuroplasticity fail to provide empirical evidence of multiple realization, its inability to do so strengthens the mind-body identity theory. Finally, we argue that a recently proposed identity theory called Flat Physicalism can (...) be enlisted to explain the current state of the mind-body problem more adequately. (shrink)

In this dissertation, I try to answer the following somewhat Kantian question: How is mental causation possible? For the discussion of the nature of mental properties, I accept the two tenets of functionalism: the multiple realizability thesis and the functional conception of mental properties as causal intermediaries between physical causes and effects. I then introduce the following two principles: the principle of physical realization and the principle of causal power identity. It is the principle of physical realization that dictates (...) that every mental property be physically realized for its instantiation. The principle of causal power identity ensures that the causal power of a mental property is identical with those of its physical realizers. I suggest that the realization relation between the mental and the physical be understood in such a way that a mental property has causal powers identical with those of its physical realizers, but that the mental property itself is not reduced to its physical realizers because the two kinds of properties are not identical. Mental properties are realized in physical properties, and the causal powers of mental properties are identical with those of physical properties; therefore, mental properties are as causally efficacious as their physical realizers. Since mental properties are not reducible to physical properties, they enjoy autonomy with the full causal powers of their realizers. To conclude, mental properties do not lose out to epiphenomenalism; and they have their own autonomy. (shrink)

This paper provides some responses to Tom Polger and Larry Shapiro’s The Multiple Realization Book (2016). I first provide a description of the authors’ framework for thinking about multiple realization and the conditions they claim this involves. I explain what I think they get right and what they get wrong with this framework. After this, I then consider a few examples of multiple realization they discuss and the interpretations they offer. While I am sympathetic to several things (...) they say about multiple realization, I also think there are some questions that have yet to be answered. (shrink)

I argue that the subset theory of property realization cannot account for both the multiple realizability and causal efficacy of mental properties. It avoids the threat of causal exclusion by identifying every power of a realized property with some power of its realizer, but this entails that the different realizers of a multiply realizable property share their causal powers, and this just isn't so. A counterexample is produced as evidence. Thus, in its original form, the theory fails to account (...) for the multiple realizability of mental properties. The theory can be amended to account for multiple realizability, but these amendments undermine its account of mental causation and thereby reintroduce the problem of causal exclusion. The subset theory is thus caught between the horns of a familiar dilemma for physicalist theories of mind. (shrink)

This article critiques R. Keith Sawyer’s theory of social causation from his 2005 book Social Emergence. It considers his use of analogy with the philosophy of mind, his account of individual agency, the legacy of Emile Durkheim, the concepts of supervenience, multiple realization, and wild disjunction, and the role of history in social causation. Sawyer’s theory is also evaluated in terms of two examples of empirical research: his own micro-sociological studies into group creativity; and Margaret Archer’s macro-sociology of education (...) systems. (shrink)

Sometimes neuroscientists discover distinct realizations for a single psychological property. In considering such cases, some philosophers have maintained that scientists will abandon the single multiply realized psychological property in favor of one or more uniquely realized psychological properties. In this paper, we build on the Dimensioned theory of realization and a companion theory of multiple realization to argue that this is not the case. Whether scientists postulate unique realizations or multiple realizations is not determined by the neuroscience alone, (...) but by the psychological theory under examination. Thus, one might say that, in the splitting or non-splitting of properties, psychology enjoys a kind of autonomy from neuroscience. (shrink)

A biogenetic structural explanation is offered for the cross‐culturally common mystical experience called portalling, the experience of moving from one reality to another via a tunnel, door, aperture, hole, or the like. The experience may be evoked in shamanistic and meditative practice by concentration upon a portalling device (mirror, mandala, labyrinth, skrying bowl, pool of water, etc.). Realization of the portalling experience is shown to be fundamental to the phenomenology underlying multiple reality cosmologies in traditional cultures and is explained (...) in terms of radical re‐entrainment of the neurological systems mediating experience in the brain. Phenomenological experiments with mirror portalling devices from both the Tibetan and the Tsimshian religious traditions are reported. (shrink)

Inter-level mechanistic explanations in the sciences have long been a focus of philosophical interest, but attention has recently turned to the compositional character of these explanations which work by explaining higher level entities, whether processes, individuals or properties, using the lower level entities they take to compose them. However, we still have no theoretical account of the constitution or parthood relations between individuals deployed in such explanations, nor any accounts of multiple constitution. My primary focus in this paper is (...) to outline a positive account of the constitution/part-whole relations between individuals posited in inter-level mechanistic explanations that takes constituents in the sciences to be ‘working parts’. Using this account, I then go on to illuminate the nature, and varieties, of multiple constitution that we find in the sciences and provide a starting theoretical framework for multiple constitution as well. (shrink)