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)

The idea of reduction has appeared in different forms throughout the history of science and philosophy. Thales took water to be the fundamental principle of all things; Leucippus and Democritus argued that everything is composed of small, indivisible atoms; Galileo and Newton tried to explain all motion with a few basic laws; 17th century mechanism conceived of everything in terms of the motions and collisions of particles of matter; British Empiricism held that all knowledge is, at root, experiential knowledge; (...) current physicists are searching for the GUT, the “grand unified theory,” that will show that at very high energies the electromagnetic and the weak and strong nuclear forces are fused into a single unified field. Some of these projects are clearly ontological in nature (Leucippus and Democritus), others are more methodological (mechanism), and still others strive for theoretical simplification (the projects of Galileo and Newton or the search for a GUT). Nevertheless, as they all aim at revealing some kind of unity or simplicity behind the appearance of plurality or complexity, they may all be regarded as (attempted) reductions. (shrink)

Philosophers have argued that on the prevailing theory of mind, functionalism, the fact that mental states are multiply realizable or can be instantiated in a variety of different physical forms, at least in principle, shows that materialism or physical is probably false. A similar argument rejects the relevance to psychology of connectionism, which holds that mental states are embodied and and constituted by connectionist neural networks. These arguments, I argue, fall before reductios ad absurdam, proving too much -- they (...) apply as well to genes, which are multiply realizable, but the reduction of which to DNA is one the core cases of scientific reductive explanation, a reduction if anything is. -/- I suggest that psychology, like biology, be what I call "provincialized," abandon claims to universal validity, except as an idealization, and treat different classes of cognizers differently from an an explanatory perspective. This would permit specifies specific, or more precisely, provincial reductions of different psychologies that might be multiply realized if such reductions were available. Connectionism may be the foundation of a reduction of human psychology, and thus biology and connectionism retain their relevance to psychology, and physicalism or materialism is consistent with functionalism. (shrink)

Mario Villalobos and Pablo Razeto-Barry argue that enactivists should understand living beings not as autopoietic systems, but as autopoietic bodies. In doing so, they surrender the principle of multiple realizability of the spatial location of living beings. By way of counterexample, I argue that more motivation is required before this principle is surrendered.

Mental causation, though a forceful intuition embedded in our commonsense psychology, is difficult to square with the rest of commitments of physicalism about the mind. Advocates of mental causation have found solace in the causal inheritance principle, according to which the mental properties of mental statesshare the causal powers of their physical counterparts. In this paper, I present a variety of counterarguments to causal inheritance and conclude that the conditions for causal inheritance are stricter than what standing versions of (...) said principle imply. In line with this, physicalism may be destined to epiphenomenalism unless multiple realizability turns out false. (shrink)

This paper aims to show that the distinction between two types of body, which is sometimes appealed to in order to clear up the Aristotelian definition of soul, sheds some light on the ontological status of prostheses and on the issue of the “multiple realizability” of life-functions. After discussing the strain that the definition of soul imposes upon the basic hylomorphic categories, the paper turns to the idea of a “functionally defined body”, whose organs are defined by the (...) power to perform their proper functions. This way of talking about the body suggests that Aristotle is committed to a principle of Functional Definition, which allows him to decide dubious cases of kind-membership solely on the basis of the presence or absence of the relevant powers – i.e., without drawing on any further considerations. The paper argues that even if that criterion seems unable to avoid the inclusion of artificial items under the same kinds as their biological counterparts, Aristotle’s philosophy of nature provides independent reasons for rejecting that unwelcome result of Functional Definition. Given the Aristotelian recognition of strong natural unities, which are “one” not because of their material continuity but because of partaking in the same principle of change, artificial limbs cannot be equated with their models. Accordingly, they perfom the same task, but in a sui generis way. (shrink)

We study the dynamical behavior of multiple quasi-synchronization of a type of fractional-order coupled neural networks with delay and uncertain parameters. By utilizing the pinned pulse control strategy technique, we establish a new pulse controller, which realizes the multiple quasisynchronization of the system. Furthermore, we derive some new criteria of multiple quasisynchronization by using the comparison principle and mathematical analysis. Eventually, simulations are carried out with two examples to explicate the effectiveness of the conclusions.

Computationalism, a specie of functionalism, posits that a mental state like pain is realized by a ‘core’ computational state within a particular causal network of such states. This entails that what is realized by the core state is contingent on events remote in space and time, which puts computationalism at odds with the locality principle of physics. If computationalism is amended to respect locality, then it posits that a type of phenomenal experience is determined by a single type of (...) computational state. But a computational state, considered by itself, is of no determinate type—it has no particular symbolic content, since it could be embedded in any of an infinite number of algorithms. Hence, if locality is respected, then the type of experience that is realized by a computational state, or whether any experience at all is realized, is under-determined by the computational nature of the state. Accordingly, Block’s absent and inverted qualia arguments against functionalism find support in the locality principle of physics. If computationalism denies locality to avoid this problem, then it cannot be considered a physicalist theory since it would entail a commitment to phenomena, like teleological causation and action-at-a-distance, that have long been rejected by modern science. The remaining theoretical alternative is to accept the locality principle for macro events and deny that formal, computational operations are sufficient to realize a phenomenal mental state. (shrink)

We propose an extension of Aczel's constructive set theory CZF by an axiom for inductive types and a choice principle, and show that this extension has the following properties: it is interpretable in Martin-Löf's type theory. In addition, it is strong enough to prove the Set Compactness theorem and the results in formal topology which make use of this theorem. Moreover, it is stable under the standard constructions from algebraic set theory, namely exact completion, realizability models, forcing as (...) well as more general sheaf extensions. As a result, methods from our earlier work can be applied to show that this extension satisfies various derived rules, such as a derived compactness rule for Cantor space and a derived continuity rule for Baire space. Finally, we show that this extension is robust in the sense that it is also reflected by the model constructions from algebraic set theory just mentioned. (shrink)

The multiple-realizability argument has been the mainstay of anti-reductionist consensus in philosophy of mind for the past thirty years. Reductionist opposition to it has sometimes taken the form of the Disjunctive Move: If mental types are multiply-realizable, they are not coextensive with physical types; they might nevertheless be coextensive with disjunctions of physical types, and those disjunctions could still underwrite psychophysical reduction. Among anti-reductionists, confidence is high that the Disjunctive Move fails; arguments to this effect, however, often leave (...) something to be desired. I raise difficulties for one anti-reductionist response to the Disjunctive Move, the Explanatory Response. (shrink)

The claim of the multiple realizability of mental states by brain states has been a major feature of the dominant philosophy of mind of the late 20th century. The claim is usually motivated by evidence that mental states are multiply realized, both within humans and between humans and other species. We challenge this contention by focusing on how neuroscientists differentiate brain areas. The fact that they rely centrally on psychological measures in mapping the brain and do so in (...) a comparative fashion undercuts the likelihood that, at least within organic life forms, we are likely to find cases of multiply realized psychological functions. (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 multiple time scales. (shrink)

This paper concerns what Jerry Fodor calls a 'metaphysical mystery': How can there by macroregularities that are realized by wildly heterogeneous lower level mechanisms? But the answer to this question is not as mysterious as many, including Jaegwon Kim, Ned Block, and Jerry Fodor might think. The multiple realizability of the properties of the special sciences such as psychology is best understood as a kind of universality, where 'universality' is used in the technical sense one finds in the (...) physics literature. It is argued that the same explanatory strategy used by physicists to provide understanding of universal behavior in physics can be used to explain how special science properties can be heterogeneously multiply realized. (shrink)

Multiply realizable properties are those whose realizers are physically diverse. It is often argued that theories which contain them are ipso facto irreducible. These arguments assume that physical explanations are restricted to the most specific descriptions possible of physical entities. This assumption is descriptively false, and philosophically unmotivated. I argue that it is a holdover from the late positivist axiomatic view of theories. A semantic view of theories, by contrast, correctly allows scientific explanations to be couched in the most perspicuous, (...) powerful language available. On a semantic view, traditional notions of multiple realizability are thus very hard to motivate. At best, one must abandon either the idea that multiple realizability is an interesting scientific notion, or else admit that multiply realizable properties do not automatically block scientific reductions. (shrink)

Reductionism and antireductionism are among the most largely and hotly debated topics in philosophy of biology today. In this section of the volume, aiming to convey the current situation in the philosophy of the natural and life sciences, these topics are specifically addressed in Mehmet Elgin’s paper, focusing on biochemistry. Elgin strongly supports reductionism, first by claiming that the now classical argument based on multiple realizability does not entail anti-reductionism and secondly highlighting how the version of methodological reductionism (...) that biochemistry has been adopting – centered on “the principle that biological functions of biomolecules in living cells can be understood in terms of chemical and physical properties of those molecules”1 – has proved largely successful, teaching “us new knowledge about the biological systems”. Taken together, these two arguments are deemed to provide good grounds for a thorough defence of reductionism. While Elgin chooses biochemistry as his privileged standpoint on the issue, I shall dwell on the stances emerging in the health sciences. Although the health sciences are closely intertwined with – amongst others – biology and biochemistry, they also have their own peculiar features. Referring to some examples taken from different medical disciplines, I will question whether reductionism can be regarded as not only a viable, option, but as the best solution to gain new knowledge about biomedical systems. I shall suggest that considerations arising from current medical research and practice support a pluralistic approach to the topic, in which both reductionist and antireductionist stances can be accommodated in different ways. (shrink)

The ‘Mind-Upload’ hypothesis, a radical version of the Brain-in-a-Vat thought experiment, asserts that a whole mind can safely be transferred from a brain to a digital device, after being exactly encoded into substrate independent informational patterns. Prima facie, MU seems the philosophical archenemy of the Embodied Mind theory, which understands embodiment as a necessary and constitutive condition for the existence of a mind and its functions. In truth, whether and why MU and EM are ultimately incompatible is unobvious. This paper, (...) which aims to answer both questions, will not simply confirm that MU and EM actually are incompatible. It will also show the true reason of their incompatibility: while EM implies that a mind’s individual identity is contingent upon the details of its physical constituents, MU presupposes that minds can be relocated from one material vessel to another. A systematic comparison between these conflicting assumptions reveals that the real shortcoming of MU is not the one usually discussed by the philosophical literature: it has nothing to do with MU’s functionalist or computationalist prerequisites, and is only secondarily related to the artificial implementability of consciousness; the real problem is that MU presupposes that minds could still be individuated and numerically identified while being reduced to immaterial formal patterns. EM seems committed to refute this assumption, but does it have sufficient resources to succeed? (shrink)

Multiple realizability says that the same kind of mental states may be manifested by systems with very different physical constitutions. Putnam ( 1967 ) supposed it to be “overwhelmingly probable” that there exist psychological properties with different physical realizations in different creatures. But because function constrains possible physical realizers, this empirical bet is far less favorable than it might initially have seemed, especially when we take on board the richer picture of neural and brain function that neuroscience has (...) been uncovering over the past forty years, in which all sorts of brain activities play crucial roles beyond all-or-nothing electrical signaling. Because of its evolutionary history, the brain’s metabolic and informational processes are inextricably intertwined. The resulting complex integrated functions impose more constraints on possible realizers than the clean, single-purpose functions usually cited as examples in discussions of multiple realizability—with ramifications for the functionalist and computationalist foundations of cognitive science, artificial intelligence, and the philosophy of mind. (shrink)

It is often claimed that the social sciences cannot be reduced to a lower-level individualistic science. The standard argument for this position is the Fodorian multiple realizability argument. Its defenders endorse token–token identities between “higher-level” social objects and pluralities/sums of “lower-level” individuals, but they maintain that the properties expressed by social science predicates are often multiply realizable, entailing that type–type identities between social and individualistic properties are ruled out. In this paper I argue that the multiple (...) class='Hi'>realizability argument for explanatory holism is unsound. The social sciences are indeed irreducible, but the principled reason for this is that the required token–token identifications cannot in general be carried through. In consequence, paradigmatic social science predicates cannot be taken to apply to the objects quantified over in the lower-level sciences. The result is that typical social science predicates cannot even be held to be co-extensive with individualistic predicates, which means type–type identifications are ruled out too. Multiple realizability has nothing to do with this failure of co-extensiveness, because the relevant social science predicates are not multiply realized in the sense intended by the explanatory holists, a sense which presupposes reductive token–token identifications. (shrink)

We have two aims. The main one is to expound the idea of renormalization in quantum field theory, with no technical prerequisites. Our motivation is that renormalization is undoubtedly one of the great ideas—and great successes--of twentieth-century physics. Also it has strongly influenced in diverse ways, how physicists conceive of physical theories. So it is of considerable philosophical interest. Second, we will briefly relate renormalization to Ernest Nagel's account of inter-theoretic relations, especially reduction. One theme will be a contrast between (...) two approaches to renormalization. The old approach, which prevailed from ca. 1945 to 1970, treated renormalizability as a necessary condition for being an acceptable quantum field theory. On this approach, it is a piece of great good fortune that high energy physicists can formulate renormalizable quantum field theories that are so empirically successful. But the new approach to renormalization explains why the phenomena we see, at the energies we can access in our particle accelerators, are described by a renormalizable quantum field theory. For whatever non-renormalizable interactions may occur at yet higher energies, they are insignificant at accessible energies. Thus the new approach explains why our best fundamental theories have a feature, viz. renormalizability, which the old approach treated as a selection principle for theories. That is worth saying since philosophers tend to think of scientific explanation as only explaining an individual event, or perhaps a single law, or at most deducing one theory as a special case of another. Here we see a framework in which there is a space of theories. And this framework is powerful enough to deduce that what seemed “manna from heaven” is to be expected: the good fortune is generic. We also maintain that universality, a concept stressed in renormalization theory, is essentially the familiar philosophical idea of multiple realizability; and that it causes no problems for reductions of a Nagelian kind. (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)

In recent decades, a number of authors have relied on the multiple realizability argument to reject methodological individualism. In this article, I argue that this strategy results in serious difficulties and makes it impossible to identify social entities and phenomena.

Multiple realizability is a key issue in debates over the nature of mind and reduction in the sciences. The subject consists of two parts:.

Bechtel and Mundale (1999) argue that multiple realizability is not plausible. They point out that neuroscientists assume that psychological traits are realized similarly in homologous brain structures and contend that a biological aspect of the brain that is relevant to neuropsychological state individuation provides evidence against multiple realizability. I argue that Bechtel and Mundale adduce the wrong sort of evidence against multiple realizability. Homologous traits do not provide relevant evidence. It is homoplasious traits of (...) brains that can provide evidence for or against multiple realizability. (shrink)

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)

We critically analyze Alexander Rosenberg’s argument based on the multiple realizability of biological properties that there are no biological laws. The argument is intuitive and suggestive. Nevertheless, a closer analysis reveals that the argument rests on dubious assumptions about the nature of natural selection, laws of nature, and multiple realizability. We also argue that the argument is limited in scope, since it applies to an outmoded account of laws and the applicability of the argument to other (...) more promising accounts of laws is questionable. Another concern of ours is that the relation between multiple realizability and natural selection is more complex than Rosenberg acknowledges. Finally, we claim that an explanation for why Rosenberg’s argument appears persuasive and appealing is that the argument is based on an inflated concept of multiple realizability that rests on unreliable intuitions concerning what counts as a different realization of the same property. Consequently, we argue that the argument is at best inconclusive and at worst false insofar as its implications for the existence of biological laws are concerned. (shrink)

A number of influences have combined to make reductionism an unpopular position in recent philosophy of mind and psychology. Davidson’s Principle of the Anomalousness of the Mental, the multiple realizability arguments of Putnam, Fodor, and others, and attempts to characterize supervenience or dependency as the appropriate nonreductive relation to seek between psychological and physical kinds are the most well-known objections. And these have found their mark. Being a psychophysical reductionist nowadays, as Jaegwon Kim aptly puts it, “is (...) a bit like being a logical positivist or a member of the Old Left—an aura of doctrinaire naiveté hangs over such a person”. (shrink)

Jerry Fodor has argued that the multiple realizability argument, as discussed in his original “Special Sciences” article, “refutes psychophysical reductionism once and for all.” I argue that his argument in “Special Sciences” does no such thing. Furthermore, if one endorses the physicalism that most supporters of the “Special Sciences” view endorse, special science laws must be reducible, in principle. The compatibility of MR with reduction, however, need not threaten the autonomy of the special sciences.

The multiple-realizability argument has been the mainstay ofanti-reductionist consensus in philosophy of mind for the past thirty years. Reductionist opposition to it has sometimes taken the form of the Disjunctive Move: If mental types are multiply-realizable, they are not coextensive with physical types; they might nevertheless be coextensive with disjunctionsof physical types, and those disjunctions could still underwrite psychophysical reduction. Among anti-reductionists, confidence is high that the Disjunctive Move fails; arguments to this effect, however, often leave something to (...) be desired. I raise difficulties for one anti-reductionist response to the DisjunctiveMove, the Explanatory Response. (shrink)

Reductionism is often understood to include two theses: (1) every singular occurrence that the special sciences can explain also can be explained by physics; (2) every law in a higher-level science can be explained by physics. These claims are widely supposed to have been refuted by the multiple realizability argument, formulated by Putnam (1967, 1975) and Fodor (1968, 1975). The present paper criticizes the argument and identifies a reductionistic thesis that follows from one of the argument's premises.

It has been debated what implications multiple realizability has for reductionism. I claim that more explicit attention needs to be paid to the distinction between multiple realizations of kinds and diverse implementations of laws. In this paper, I distinguish two different theses on the relations between multiple realization and diverse implementation: one thesis states that multiple realizations imply diverse implementations and the other states the converse. I claim that although antireductionism might turn out to be (...) false if the first thesis is accepted, this “realization‐based” antireductionism is not the only option for antireductionism. For the antireductionists who accept the second thesis, multiple realizations only provide evidence for diverse implementations. I defend this “implementation‐based” antireductionism again Shapiro's dilemma. I argue that one horn of the dilemma does not pose any problem and that the other horn simply begs the question. (shrink)

Biological theory demands a clear organism concept, but at present biologists cannot agree on one. They know that counting particular units, and not counting others, allows them to generate explanatory and predictive descriptions of evolutionary processes. Yet they lack a unified theory telling them which units to count. In this paper, I offer a novel account of biological individuality, which reconciles conflicting definitions of ‘organism’ by interpreting them as describing alternative realisers of a common functional role, and then defines individual (...) organisms as essentially possessing some mechanisms that play this role. (shrink)

Multiple Realizability (MR) must still be regarded as one of the principal arguments against type reductionist accounts of higher-order properties and their special laws. Against this I argue that there is no unique MR but rather a multitude of MR categories. In a slogan: MR is itself “multi-realized”. If this is true then we cannot expect one unique reductionist strategy against MR as an anti-reductionist argument. The main task is rather to develop a taxonomy of the wide variety (...) of MR cases and to sketch possible reductionist answers for each class of cases. The paper outlines some first steps in this direction. (shrink)

This article examines the multiple realizability thesis within a causal framework. The beginnings of this framework are found in Elliott Sober’s “Multiple Realizability Argument against Reduction,”...

I will discuss two possible options how a defender of the type identity-theory with respect to mental properties can avoid the conclusion of Putnam's Multiple Realizability Argument. I begin by offering a rigorous formulation of Putnam's argument, which has been lacking so far in the literature (section 2). This rigorous formulation shows that there are basically two possible options for avoiding the argument's conclusion. Contrary to current mainstream, I reject the first option?Kim's 'local reductionism'?as untenable (section 3). I (...) endorse the second option, which has been brought into discredit by being too closely associated with disjunctive properties. I first show that many of the criticisms of disjunctive properties miss their target or beg the question against their opponent view (sections 4 & 5). Then I argue that it is not necessary to tie the second option closely to disjunctive properties. Hence, even if we deny the legitimacy of disjunctive properties, the identity-theorist still need not accept the conclusion of the Multiple Realizability Argument since there is an alternative, though related, way to spell out the second response (section 6). (shrink)

Framed within the dialectic of the causal exclusion argument (Kim 2005), this paper does two things. One, it clarifies some properties of multiple realizability based on its true origin (Turing 1950). And two, it challenges a form of argument Noordhof (1997), Clarke (1999), and Whittle (2007) employ to support the idea that the mental has causal powers not had by its physical realization base (Novel). The paper challenges Novel with ideas derived from multiple realizability, among others.

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)

A popular argument supporting functionalism has been what is commonly called the “multiple realizability” argument. One version of this argument uses thought experiments designed to show that minds could be composed of different types of material. This article offers a metaphilosophical analysis of this argument and shows that it fails to provide a strong case for functionalism. The multiple realizability argument is best understood as an inference‐to‐the‐best‐explanation argument, whereby a functionalist account of our mental concepts serves (...) to explain our multiple realizability intuitions. I show that the argument is inadequate because alternative accounts of our mental concepts exist that provide equally plausible explanations for these intuitions. Moreover, in the case of our qualia concepts, a nonfunctionalist account explains several other intuitions that functionalism cannot explain. Thus, despite its popularity, the intuition‐based version of the multiple realizability argument is a poor reason for accepting functionalism. (shrink)

b>: This article explains the concept of multiple realizability and its role in the philosophy of mind. In particular, I consider what is required for the multiple realizability of psychological kinds, the relevance of multiple realizability to the reducibility and autonomy of psychology, as well as further refinements of the concept that would prove helpful.

The claim of the multiple realizability of mental states by brain states has been a major feature of the dominant philosophy of mind of the late 20th century. The claim is usually motivated by evidence that mental states are multiply realized, both within humans and between humans and other species. We challenge this contention by focusing on how neuroscientists differentiate brain areas. The fact that they rely centrally on psychological measures in mapping the brain and do so in (...) a comparative fashion undercuts the likelihood that, at least within organic life forms, we are likely to find cases of multiply realized psychological functions. (shrink)

The argument from multiple realizability is that, because quite diverse physical systems are capable of giving rise to identical psychological phenomena, mental states cannot be reduced to physical states. This influential argument depends upon a theory of reduction that has been defunct in the philosophy of science for at least fifteen years. Better theories are now available.

Tononi has proposed a fundamental theory of consciousness he terms Integrated Information Theory (IIT). IIT purports to explain the quantity of conscious experience by linking it with integrated information: information shared by the system as a whole and quantified by adopting a modified version of Shannon's definition of information. Since the fundamental aspect of IIT is information the theory allows for the multiple realizability of consciousness. While there are several concepts within IIT that need further theoretical development, the (...) main failings of the theory are an absence of a link between conscious experience and awareness and the use of Shannon's limited data based definition of information. These limitations prevent the theory from satisfying Chalmers' principles of structural coherence and organizational invariance which any functionalist theory should obey. It is not clear whether IIT can be repaired without simply reducing the theory to a general statement of computational functionalism. (shrink)

Must a theory of quantum gravity have some truth to it if it can recover general relativity in some limit of the theory? This paper answers this question in the negative by indicating that general relativity is multiply realizable in quantum gravity. The argument is inspired by spacetime functionalism—multiple realizability being a central tenet of functionalism—and proceeds via three case studies: induced gravity, thermodynamic gravity, and entanglement gravity. In these, general relativity in the form of the Einstein field (...) equations can be recovered from elements that are either manifestly multiply realizable or at least of the generic nature that is suggestive of functions. If general relativity, as argued here, can inherit this multiple realizability, then a theory of quantum gravity can recover general relativity while being completely wrong about the posited microstructure. As a consequence, the recovery of general relativity cannot serve as the ultimate arbiter that decides which theory of quantum gravity that is worthy of pursuit, even though it is of course not irrelevant either qua quantum gravity. Thus, the recovery of general relativity in string theory, for instance, does not guarantee that the stringy account of the world is on the right track; despite sentiments to the contrary among string theorists. (shrink)

Shapiro has argued that the multiple realizability thesis for psychology, despite its broad acceptance, is far from being a well-established thesis. He suggests that not only do many of the standard examples of multiple realizability fail to be clearly examples but a competing thesis (“the mental constraint thesis”) that human-like minds are severely constrained in their physical realization is the more likely thesis. I will argue, however, that Shapiro’s mental constraint thesis is not a competing thesis (...) with the multiple realizability thesis. Once it is understood how these theses are compatible, the widespread acceptance of multiple realizability looks entirely reasonable. (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)