Multiple realizability (MR) is traditionally conceived of as the feature of computational systems, and has been used to argue for irreducibility of higher-level theories. I will show that there are several ways a computational system may be seen to display MR. These ways correspond to (at least) five ways one can conceive of the function of the physical computational system. However, they do not match common intuitions about MR. I show that MR is deeply interest-related, and for this reason, difficult (...) to pin down exactly. I claim that MR is of little importance for defending computationalism, and argue that it should rather appeal to organizational invariance or substrate neutrality of computation, which are much more intuitive but cannot support strong antireductionist arguments. (shrink)

ABSTRACT Proponents of mechanistic explanation have recently suggested that all explanation in the cognitive sciences is mechanistic, even functional explanation. This last claim is surprising, for functional explanation has traditionally been conceived as autonomous from the structural details that mechanistic explanations emphasize. I argue that functional explanation remains autonomous from mechanistic explanation, but not for reasons commonly associated with the phenomenon of multiple realizability. 1Introduction 2Mechanistic Explanation: A Quick Primer 3Functional Explanation: An Example 4Autonomy as Lack of Constraint 5The Price (...) of Autonomy 6Another Argument against Autonomy 7Conclusion: Autonomy and Multiple Realization. (shrink)

What is the relationship between pain and the body? I claim that pain is best explained as a type of personal experience and the bodily response during pain is best explained in terms of a type of mechanical neurophysiologic operation. I apply the radical philosophy of identity theory from philosophy of mind to the relationship between the personal experience of pain and specific neurophysiologic mechanism and argue that the relationship between them is best explained as one of type identity. Specifically, (...) pain is a specific type of personal experience identical to a specific type of allostatic stress response comprised of interdependent nervous, endocrine and immune mechanical operations. (shrink)

In the literature on multiple realizability and the identity theory, cases of neural plasticity have enjoyed a very limited role. The present article attempts to remedy this small influence by arguing that clinical and experimental evidence of quite extensive neural reorganization offers compelling support for the claim that psychological kinds are multiply realized in neurological kinds, thus undermining the identity theory. In particular, cases are presented where subjects with no measurable psychological deficits also have vast, though gradually received, neurological damage. (...) Common objections and concerns are also discussed and rejected. 1 Introduction2 The GRP, Serial Lesion Effect, and Multiple Realizability2.1 A case study of the serial lesion effect2.2 Evaluating the case study’s evidence for multiple realizability3 The GRP More Generally4 Objections to the GRP as Evidence for Multiple Realizability4.1 Small plastic effects and neurological taxonomies4.2 But do neural regions and locations even matter at all?4.3 But are there not other options besides location?5 Conclusion. (shrink)

Saying that psychological states are functional states, the functionalist claims more than that psychological states have functions. Rather, functionalism is the theory that psychological states are defined and constituted by their functions. On this view, what it is to be a psychological state of a certain sort just is and consists entirely of having a certain function. Anything that has that function in a suitable system would therefore be that psychological state. If storing information for later use is the essential (...) function of memory, then anything that has that function counts as a memory. Similarly, one might say that anything that traps or kills mice counts as a mouse trap. (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)

Identity theories are those that hold that 'sensations are brain processes'. In particular, they hold that mental/psychological state kinds are identical to brain/neuroscientific state kinds. In this paper, I isolate and explain some of the key features of contemporary identity theories. They are then contrasted with the main live alternatives by means of considering the two most important lines of objection to identity theories.

I identify a class of arguments against multiple realization (MR): BookofSand arguments. The arguments are in their general form successful under reasonably uncontroversial assumptions, but this, on the other hand, turns the table on identity theory: If arguments from MR can always be refuted by BookofSand arguments, is identity theory falsifiable? In the absence of operational demarcation criteria, it is not. I suggest a parameterized formal demarcation principle for brain state/process types and show how it can be used to identify (...) previously unconsidered contenders for evidence for MR, e.g., binary classification, division, and sorting. For these to be actual instances of MR, the corresponding psychological kinds must be verifiably, relevantly similar. I also briefly discuss possible linguistic, behavioral, and experimental demarcation criteria for psychological kinds. (shrink)

Current orthodoxy takes representation to be essential to computation. However, a philosophical account of computation that does not appeal to representation would be useful, given the difficulties involved in successfully theorizing representation. Piccinini's recent mechanistic account of computation proposes to do just that: it couches computation in terms of what certain mechanisms do without requiring the manipulation or processing of representations whatsoever (Piccinini 2015). Most crucially, mechanisms must process medium-independent vehicles. There are two ways to understand what "medium-independence" means on (...) this account; however, on either understanding, the account fails. Either too many things end up being counted as computational, or purportedly natural computations (e.g., neural computations) cannot be counted at all. In the end, illustrating this failure sheds some light on the way to revise the orthodoxy in the hope of a better account of computation. (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)

Philosophers look to the realization relation as a way to make sense of the possibility that special science kinds are physical, yet not reducible to kinds in physics. A realized property fails to reduce because it can be realized in multiple ways, thus blocking its identification with lower-level properties. One prominent analysis of realization, subset realization, distinguishes multiple realizers on the basis their “left-over powers,” that is, those that don’t contribute to the individuative powers of the realizer. However, I argue, (...) the subset analysis of realization fails to mark an important distinction between different ways that a property might be realized, and also makes questions about the reducibility of kinds—presumably an empirical issue—tractable from the armchair. I offer as an alternative mechanistic multiple realization, which avoids both these problems. (shrink)

Thomas Polger and Lawrence Shapiro claim that unlike human-made artifacts cases of multiple realization in naturally occurring systems are uncommon. Drawing on cases from systems biology, I argue t...

It has often been thought that compositional variation across systems that are similar from the point of view of the special sciences provides a key point in favor of the multiple realization of special science kinds and in turn the broadly nonreductive consequences often thought to follow from multiple realization. Yet in a series of articles, and culminating in The Multiple Realization Book, Tom Polger and Larry Shapiro argue that an account of multiple realization demanding enough to yield such nonreductive (...) consequences implies that compositional variation is far less significant for the multiple realization of special science kinds than many have supposed. I argue, in contrast, that even on this demanding account, lower-level compositional variation may frequently support the multiple realization of special science kinds across the systems of interest, and that there is a good explanation for where Polger and Shapiro go wrong in drawing the contrary conclusion. I consider but reject Carl Gillett’s claim that different views about the significance of compositional variation for multiple realization phenomena should be traced to implicit disagreement about the metaphysics of realization. (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)

Researchers in the cognitive sciences often seek neural correlates of psychological constructs. In this paper, I argue that even when these correlates are discovered, they do not always lead to reductive outcomes. To this end, I examine the psychological construct of a critical period and briefly describe research identifying its neural correlates. Although the critical period is correlated with certain neural mechanisms, this does not imply that there is a reductionist relationship between this psychological construct and its neural correlates. Instead, (...) this case study suggests that there may be many-to-many psychological-neural mappings, not just one-to-one or even one-to-many relations between psychological kinds and types of neural mechanisms. (shrink)

We sketch a framework for building a unified science of cognition. This unification is achieved by showing how functional analyses of cognitive capacities can be integrated with the multilevel mechanistic explanations of neural systems. The core idea is that functional analyses are sketches of mechanisms , in which some structural aspects of a mechanistic explanation are omitted. Once the missing aspects are filled in, a functional analysis turns into a full-blown mechanistic explanation. By this process, functional analyses are seamlessly integrated (...) with multilevel mechanistic explanations. (shrink)

Fifty years ago J. J. C. Smart published his pioneering paper, “Sensations and Brain Processes.” It is appropriate to mark the golden anniversary of Smart’s publication by considering how well his article has stood up, and how well the identity theory itself has fared. In this paper I first revisit Smart’s text, reflecting on how it has weathered the years. Then I consider the status of the identity theory in current philosophical thinking, taking into account the objections and replies that (...) Smart discussed as well as some that he did not anticipate. Finally, I offer a brief manifesto for the identity theory, providing a small list of the claims that I believe contemporary identity theorist should accept. As it turns out, these are more or less the ones that Smart defended fifty years ago. (shrink)

Proponents of mechanistic explanation have argued that dynamical models are mere phenomenal models, in that they describe rather than explain the scientific phenomena produced by complex systems. I argue instead that dynamical models can, in fact, be explanatory. Using an example from neuroscientific research on epilepsy, I show that dynamical models can meet the explanatory demands met by mechanistic models, and as such occupy their own unique place within the space of explanatory scientific models.

One of the main line of responses to the infamous causal exclusion problem has been based on the counterfactual account of causation. However, arguments have begun to surface to the effect that the counterfactual theory is in fact ill-equipped to solve the exclusion problem due to its commitment to downward causation. This argumentation is here critically analysed. An analysis of counterfactual dependence is presented and it is shown that if the semantics of counterfactuals is taken into account carefully enough, the (...) counterfactual notion of causation does not need to be committed to downward causation. However, it is a further question whether this is eventually enough to solve the exclusion problem for the analysis shows how the problem itself can take various different forms. (shrink)

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)

The past two decades have witnessed a revival of interest in multiple realization and multiply realized kinds. Bechtel and Mundale’s (1999) illuminating discussion of the subject must no doubt be credited with having generated much of this renewed interest. Among other virtues, their paper expresses what seems to be an important insight about multiple realization: that unless we keep a consistent grain across realized and realizing kinds, claims alleging the multiple realization of psychological kinds are vulnerable to refutation. In this (...) paper I argue that, intuitions notwithstanding, the terms of their recommendation make it impossible to follow, while also misleadingly insinuating that its application virtually guarantees mind-brain identity. Instead of a matching of grains, what multiple realization really requires is a principled method for adjudicating upon differences between tokens. Shapiro’s (2000) work on multiple realization can be understood as an attempt to adumbrate just such a method. While his “causal relevance” criterion can easily be mistaken for Bechtel and Mundale’s grain requirement, my analysis reveals exactly where and why these two tests diverge. (shrink)

We address the commentaries on our target article in terms of four major themes. First, we note that virtually all commentators agree that mental disorders are not brain disorders in the common interpretation of these terms, and establish the consensus that explanatory reductionism is not a viable thesis. Second, we address criticisms to the effect that our article was misdirected or aimed at a straw man; we argue that this is unlikely, given the widespread communication of reductionist slogans in psychopathology (...) research and society. Third, we tackle the question of whether intentionality, extended systems, and multiple realizability are as problematic as claimed in the target article, and we present a number of nuances and extensions with respect to our article. Fourth, we discuss the question of how the network approach should incorporate biological factors, given that wholesale reductionism is an unlikely option. (shrink)

A common view is that the truth of multiple realization—e.g., about psychological states—entails the truth of functionalism. This is supposed to follow because what is multiply realized is eo ipso realized. I argue that view is mistaken by demonstrating how it misrepresents arguments from multiple realization. In particular, it undermines the empirical component of the arguments, and renders the multiplicity of the realization irrelevant. I suggest an alternative reading of multiple realizability arguments, particularly in philosophy of psychology. And I explain (...) the proper way to understand the relation between realization and multiple realization. (shrink)

Whether mental properties are identical with neural properties is one of the central questions of contemporary philosophy of mind. Many philosophers agree that even if mental properties are identical with neural properties, the mind-brain identity thesis cannot be established on empirical grounds, but only be vindicated by theoretical philosophical considerations. In his paper ‘When Is a Brain Like the Planet?’, Clark Glymour proposes a causal criterion for local property identifications and claims that this criterion can be used to empirically establish (...) local identities between mental and neural properties. If successful, such an account would settle the debate on the mind-body problem. In this paper, I argue that Glymour’s approach falls short of its aims. The causal criterion which he proposes does not provide a sufficient condition for the local identification of properties. Moreover, his account does not succeed in rendering local mind-brain identities empirically testable. Therefore, the mind-body problem cannot be solved as easily as Glymour assumes. (shrink)

Holistic views of content claim that we each speak and think in distinct and idiosyncratic idiolects: although we may often entertain thoughts with similar contents, the content of our thoughts can...

Cappelen proposes a radically externalist framework for conceptual engineering. This approach embraces the following two theses. Firstly, the mechanisms that underlie conceptual engineering are inscrutable: they are too complex, unstable and non-systematic for us to grasp. Secondly, the process of conceptual engineering is largely beyond our control. One might think that these two theses are peculiar to the Austerity Framework, or to metasemantic externalism more generally. However, Cappelen argues that there is no reason to think that internalism avoids either commitment. (...) Cappelen argues that to do so she must provide arguments for 3 claims: there are inner states that are scrutable and within our control; concepts supervene on these inner states; and the determination relation from supervenience base to content is itself scrutable and within our control. In this paper, I argue that internalist conceptual role theories of content can meet Cappelen’s challenge. (shrink)

The view that special science properties are multiply realizable has been attacked in recent years by Shapiro, Bechtel and Mundale, Polger, and others. Focusing on psychological and neuroscientific properties, I argue that these attacks are unsuccessful. By drawing on interspecies physiological comparisons I show that diverse physical mechanisms can converge on common functional properties at multiple levels. This is illustrated with examples from the psychophysics and neuroscience of early vision. This convergence is compatible with the existence of general constraints on (...) the evolution of cognitive systems, and does not involve any ad hoc typing of coarse-grained higher level properties. The mechanisms that realize these common higher level properties are really distinct by the criteria laid down by critics of multiple readability. Finally, I present an account of how such functional properties might constitute special science kinds by playing a central explanatory role in a range of cognitive models. Behavioral science kinds in particular are the functionally defined constituents picked out by our most successful models of the multilevel systems and mechanisms that explain cognitive capacities. (shrink)

Absence of evidence arguments are indispensable to comparative neurobiology. The absence in a given species of a homologous neural architecture strongly correlated with a type of conscious experience in humans should be able to be taken as a prima facie reason for concluding that the species in question does not have the capacity for that conscious experience. Absence of evidence reasoning is, however, widely disparaged for being both logically illicit and unscientific. This paper argues that these concerns are unwarranted. There (...) is no logical barrier to formulating cogent absence of evidence arguments; indeed, accepting such arguments is part of what it is to be committed to falsifiability as a critical aspect of the scientific method. Absence of evidence arguments can always be blocked, however, by assuming that psychological properties are ‘multiply realizable’. While we take multiple realizability to be highly likely at some level of analysis, we argue that it is question-begging to assume that it exists at every level of analysis, and thus it should not automatically be thought to undermine absence of evidence reasoning in the animal consciousness debate. Using the example of pain and focusing on homologies at the level of information processing tasks, we show how, in the science of consciousness, an absence of evidence might well serve as evidence of absence. (shrink)

Recently, several critics of the multiple realizability thesis have argued that philosophers have tended to accept the thesis on too weak grounds. On the one hand, the analytic challenge has problematized how philosophers have treated the multiple realization relation itself, claiming that assessment of the sameness of function and the relevant difference of realizers has been uncritical. On the other hand, it is argued that the purported evidence of the thesis is often left empirically unverified. This paper provides a novel (...) strategy to answer these worries by introducing a role for multiple realizability in the context of biological engineering. In the field of synthetic biology, bioengineers redesign the evolutionary realizations of biological functions, even constructing artificial chemical surrogates in the laboratory. I show how in the rational design approach to biological engineering, multiple realizability can function as a design heuristic in which the sameness of function and difference of realizers can be controlled. Although practically motivated, this engineering approach has also a theoretical, exploratory component that can be used to study the empirical limitations of multiple realizability. Successful realization of the engineering designs would amount to a concrete demonstration of multiple realizability, taking evidence for MRT beyond what is readily found in nature. (shrink)

Shapiro has suggested that the empirical plausibility of the multiple realizability of human-like minds is dubious, because a contrary thesis, the Mental Constraint Thesis, enjoys positive empirical evidence. The Mental Constraint Thesis states that, given the actual physical laws, there is only one way to realize a human-like mind. I will suggest, however, that the Mental Constraint Thesis is not a contrary to the empirical multiple realizability thesis relevant to psychological reduction or autonomy and, as a consequence, has no bearing (...) on those classificatory issues. (shrink)

Critics of multiple realizability have recently argued that we should concentrate solely on actual here-and-now realizations that are found in nature. The possibility of alternative, but unactualized, realizations is regarded as uninteresting because it is taken to be a question of pure logic or an unverifiable scenario of science fiction. However, in the biological context only a contingent set of realizations is actualized. Drawing on recent work on the theory of neutral biological spaces, the paper shows that we can have (...) ways of assessing the modal dimension of multiple realizability that do not have to rely on mere conceivability. (shrink)