Externalism and Cognitive Science

I discuss externalism from the point of view of explanatory scientific theories. I ask what externalism is supposed to explain, and whether such an explanation is or should be a scientific one. In contrast to leading externalists, I argue that whatever merits externalism may possess, it is unable to provide a fruitful explanatory framework for a scientific theory of the mind. I argue that an externalist explanation of meaning is concerned with ascription of meaning rather than the mechanisms of meaning. (...) That is, externalism is not concerned with the mental mechanisms in virtue of which humans produce and comprehend meaning. I argue that a fruitful scientific explanation is one that aims to uncover the underlying mechanisms in virtue of which the observable phenomena are made possible, and that a scientific psychology should be doing just that. Therefore, externalist explanations are not part of the cognitive psychological explanation of the mechanisms in virtue of which meaning is made possible. Rather, externalist explanations are what may be termed a philosophical-hermeneutic explanatory project in that they play an interpretive function for the theorist by linking internal psychological states and the world. (shrink)

Do our minds extend beyond our brains? In a series of publications, Mark Rowlands has argued that the correct answer to this question is an affirmative one. According to Rowlands, certain types of operations on bodily and worldly structures should be considered to be proper and literal parts of our cognitive and mental processes. In this article, I present and critically evaluate Rowlands' position.

The relation between computational and intentional psychology has always been a vexing issue. The worry is that if mental processes are computational, then these processes, which are defined over symbols, are sensitive solely to the non-semantic properties of symbols. If so, perhaps psychology could dispense with adverting in its laws to intentional/semantic properties of symbols. Stich, as is well-known, has made a great deal out of this tension and argued for a purely "syntactic" psychology by driving a wedge between a (...) semantic individuation of symbol tokens and their narrow functional individuation. If the latter can be carried out, he claimed, we do not need semantic typing. I argue that since a narrow functional individuation cannot type-identify symbol tokens across organisms, a semantic account of typing must be the only option given that interpersonal physical individuation of tokens is not to be taken seriously. (shrink)

It is widely assumed that the explanatory states of scientific psychology are type-individuated by their semantic or intentional properties. First, I argue that this assumption is implausible for theories like David Marr's [1982] that seek to provide computational or syntactic explanations of psychological processes. Second, I examine the implications of this conclusion for the debate over psychological individualism. While most philosophers suppose that syntactic states supervene on the intrinsic physical states of information-processing systems, I contend they may not. Syntatic descriptions (...) must be adequately constrained, and the most plausible such constraints appeal to a system's teleological function or design and hence to its history. As a result, physical twins may not realize the same syntactic states. (shrink)

The role of content in computational accounts of cognition is a matter of some controversy. An early prominent view held that the explanatory relevance of content consists in its supervenience on the the formal properties of computational states (see, e.g., Fodor 1980). For reasons that derive from the familiar Twin Earth thought experiments, it is usually thought that if content is to supervene on formal properties, it must be narrow; that is, it must not be the sort of content that (...) determines reference and truth-conditions. An interesting alternative to this view has recently been proposed by Egan (1995). According to Egan, the explanatory role of content is such that contents must in general be broad to be explanatorily relevant. But Egan’s view involves a non-realist interpretation of content assignments. I will argue here that this non-realism about contents is undermotivated. A realist variation on her view of the explanatory role of content, however, would survive this criticism. This realist variation, I suggest, shares with the views of other commentators on Marr’s theory (e.g., Burge 1986; Shapiro 1993; forthcoming) certain commitments concerning the supervenience base of visual contents and processes. I will argue, however, that these commitments beg important questions regarding the individuation of cognitive states and processes. I conclude, contrary to Burge and Shapiro, that Marr’s theory does not favor anti-individualism. (shrink)

Externalism about the mind holds that the explanation of our representational capacities requires appeal to mental states that are individuated by reference to features of the environment. Externalists claim that ‘narrow’ taxonomies cannot account for important features of psychological explanation. I argue that this claim is false, and offer a general argument for preferring narrow taxonomies in psychology.

Computational properties, it is standardly assumed, are to be sharply distinguished from semantic properties. Specifically, while it is standardly assumed that the semantic properties of a cognitive system are externally or non-individualistically individuated, computational properties are supposed to be individualistic and internal. Yet some philosophers (e.g., Tyler Burge) argue that content impacts computation, and further, that environmental factors impact computation. Oron Shagrir has recently argued for these theses in a novel way, and gave them novel interpretations. In this paper I (...) present a conception of computation in cognitive science that takes Shagrir's conception as its starting point, but further develops it in various directions and strengthens it. I argue that the explanatory role of computational properties emerges from the idea that syntactical properties and the relevant external factors presented by cognitive systems compose wide computational properties. I also elaborate upon the notion of content that is in play, and argue that it is contents of the kind that are ascribed by transparent interpretations of content ascriptions that impact computation. This fact enables the thesis that external factors impact computation to rebuff the challenge which concerns the claim that psychology must be individualistic. (shrink)

Abstract It is widely assumed that the meaning of at least some types of expressions involves more than their reference to objects, and hence that there may be co-referential expressions which differ in meaning. It is also widely assumed that ?syntax does not suffice for semantics?, i.e. that we cannot account for the fact that expressions have semantic properties in purely syntactical or computational terms. The main goal of the paper is to argue against a third related assumption, namely that (...) what is responsible for a difference in meaning between co-referential expressions is the computational difference in the cognitive functioning of the expressions. ?Intentional aspects? of expressions?those features which their meanings involve in addition to reference?cannot be syntacticized, since they are individuated not in terms of any cognitive feature, but rather in terms of those properties of the referents through which the expressions refer to them, and cognitive features cannot determine such properties in exactly the same sense as they cannot determine reference. (shrink)

Contemporary philosophy and theoretical psychology are dominated by an acceptance of content-externalism: the view that the contents of one's mental states are constitutively, as opposed to causally, dependent on facts about the external world. In the present work, it is shown that content-externalism involves a failure to distinguish between semantics and pre-semantics---between, on the one hand, the literal meanings of expressions and, on the other hand, the information that one must exploit in order to ascertain their literal meanings. It is (...) further shown that, given the falsity of content-externalism, the falsity of the Computational Theory of Mind (CTM) follows. It is also shown that CTM involves a misunderstanding of terms such as "computation," "syntax," "algorithm," and "formal truth." Novel analyses of the concepts expressed by these terms are put forth. These analyses yield clear, intuition-friendly, and extensionally correct answers to the questions "what are propositions?, "what is it for a proposition to be true?", and "what are the logical and psychological differences between conceptual (propositional) and non-conceptual (non-propositional) content?" Naively taking literal meaning to be in lockstep with cognitive content, Burge, Salmon, Falvey, and other semantic externalists have wrongly taken Kripke's correct semantic views to justify drastic and otherwise contraindicated revisions of commonsense. (Salmon: What is non-existent exists; at a given time, one can rationally accept a proposition and its negation. Burge: Somebody who is having a thought may be psychologically indistinguishable from somebody who is thinking nothing. Falvey: somebody who rightly believes himself to be thinking about water is psychologically indistinguishable from somebody who wrongly thinks himself to be doing so and who, indeed, isn't thinking about anything.) Given a few truisms concerning the differences between thought-borne and sentence-borne information, the data is easily modeled without conceding any legitimacy to any one of these rationality-dismantling atrocities. (It thus turns out, ironically, that no one has done more to undermine Kripke's correct semantic points than Kripke's own followers!). (shrink)

The editors introduce the themed issue “stigmergy 3.0”.

Only computational explanations of a content‐involving sort can answer certain ‘how’‐questions; can support content‐involving counterfactuals; and have the generality characteristic of psychological explanations. Purely formal characteriza‐tions of computations have none of these properties, and do not determine content. These points apply not only to psychological explanation, but to Turing machines themselves. Computational explanations which involve content are not opposed to naturalism. They are also required if we are to explain the content‐involving properties of mental states.

In this essay I defend a theory of psychological explanation that is based on the joint commitment to direct reference and computationalism. I offer a new solution to the problem of Frege Cases. Frege Cases involve agents who are unaware that certain expressions corefer (e.g. that 'Cicero' and 'Tully' corefer), where such knowledge is relevant to the success of their behavior, leading to cases in which the agents fail to behave as the intentional laws predict. It is generally agreed that (...) Frege Cases are a major problem, if not the major problem, that this sort of theory faces. In this essay, I hope to show that the theory can surmount the Frege Cases. (shrink)

It has been argued that Psychological Externalism is irrelevant to psychology. The grounds for this are that PE fails to individuate intentional states in accord with causal power, and that psychology is primarily interested in the causal roles of psychological states. It is also claimed that one can individuate psychological states via their syntactic structure in some internal "language of thought". This syntactic structure is an internal feature of psychological states and thus provides a key to their causal powers. I (...) argue that in fact any syntactic structure deserving the name will require an external individuation no less than the semantic features of psychological states. (shrink)

The paper presents an extended argument for the claim that mental content impacts the computational individuation of a cognitive system (section 2). The argument starts with the observation that a cognitive system may simultaneously implement a variety of different syntactic structures, but that the computational identity of a cognitive system is given by only one of these implemented syntactic structures. It is then asked what are the features that determine which of implemented syntactic structures is the computational structure of the (...) system, and it is contended that these features are certain aspects of mental content. The argument helps (section 3) to reassess the thesis known as computational externalism, namely, the thesis that computational theories of cognition make essential reference to features in the individual's environment. It is suggested that the familiar arguments for computational externalism?which rest on thought experiments and on exegesis of Marr's theories of vision?are unconvincing, but that they can be improved. A reconstruction of the visex/audex thought experiment is offered in section 3.1. An outline of a novel interpretation of Marr's theories of vision is presented in section 3.2. The corrected arguments support the claim that computational theories of cognition are intentional. Computational externalism is still pending, however, upon the thesis that psychological content is extrinsic. (shrink)

Throughout the text, fundamental questions concerning the nature of visual perception are addressed.

In this paper I address an important question concerning the nature of visual content: are the contents of human visual states and experiences exhaustively fixed or determined (in the non-causal sense) by our intrinsic physical properties? The individualist answers this question affirmatively. I will argue that such an answer is mistaken. A common anti-individualist or externalist tactic is to attempt to construct a twin scenario involving humanoid duplicates who are embedded in environments that diverge in such a way that it (...) appears to be necessary to attribute divergent contents to their respective visual states. In the first half of the paper I discuss some of the twin scenarios that are prominent in the literature and argue that they fail to undermine individualism. Indeed I argue that due to important facts about our internal workings, a convincing externalist twin scenario involving humanoid protagonists cannot be constructed. However, I argue that such a result does not conclusively establish an individualist thesis and that in order to settle the question at issue it is necessary to construct an independently motivated theory of visual content. I attempt to do this in the second half of the paper by developing a theory at the core of which is the idea that the contents of our visual states and experiences are determined by the causal powers vis-. (shrink)

According to one brand of 'externalism', cognitive theories should individuate mental content 'widely'--that is, partly in terms of environmental features. David Marr's theory of vision is often cited in support of this view. Many philosophers (most notably, Tyler Burge) regard it as a prime example of a fruitful cognitive theory that widely individuates the representations it posits. I argue that, contrary to popular belief, Marr's theory does not presuppose an externalist view of mental content.

David Marr's theory of vision has been widely cited by philosophers and psychologists. I have three projects in this paper. First, I try to offer a perspicuous characterization of Marr's theory. Next, I consider the implications of Marr's work for some currently popular philosophies of psychology, specifically, the "hegemony of neurophysiology view", the theories of Jerry Fodor, Daniel Dennett, and Stephen Stich, and the view that perception is permeated by belief. In the last section, I consider what the phenomenon of (...) vision must be like for Marr's project to succeed. (shrink)

The debate concerning the individuating role of the external environment in propositional content has turned to Marr’s computational theory of vision for either verification or disproof. Although not all the relevant arguments concerning the determining role of environmental constraints that Marr invokes in his visual account may succeed, the paper argues that Marr divides his computational explanation into two parts, the information processing “what” and the constraint introducing “why” aspect. It is the second part where separate claims concerning the necessity (...) and sufficiency of constraints are advocated, and initiate a specific computational process. The above explanation becomes subordinate to a conception of inference that closely resembles deduction. (shrink)

According to Marr's theory of vision, computational processes of early vision rely for their success on certain "natural constraints" in the physical environment. I examine the implications of this feature of Marr's theory for the question whether psychological states supervene on neural states. It is reasonable to hold that Marr's theory is nonindividualistic in that, given the role of natural constraints, distinct computational theories of the same neural processes may be justified in different environments. But to avoid trivializing computational explanations, (...) theories must respect methodological solipsism in the sense that within a theory there cannot be differences in content without a corresponding difference in neural states. (shrink)

Frances Egan argues that the states of computational theories of vision are individuated individualistically and, as far as the theory is concerned, are not intentional. Her argument depends on equating the goals and explanatory strategies of computational psychology with those of its algorithmic level. However, closer inspection of computational psychology reveals that the computational level plays an essential role in explaining visual processes and that explanations at this level are nonindividualistic and intentional. In conclusion, I sketch an account of content (...) in which content does the sort of explanatory work that Egan denies is possible. (shrink)

Many philosophers and psychologists who approach the issue of representation from a computational or measurement theoretical perspective end up having to deny the possibility of junk representations?representations present in an organism's head but that enter into no psychological processes or produce no behaviour. However, I argue, a more functional perspective makes the possibility of junk representations intuitively quite plausible?so much so that we may wish to question those views of representation that preclude the possibility of junk representations. I explore some (...) of the reasons we should care about the possibility of junk representations and conclude with some speculation about whether junk representations are in fact present in our heads. (shrink)

Noam Chomsky and Frances Egan argue that David Marr.

An important class of teleological theories cannot explain the representational content of visual states because they fail to address the relationship between the world, projected retinal stimuli, and perception. A different approach for achieving a naturalized theory of visual content is offered that rejects the traditional internalism/externalism debate in favor of what is termed “empirical externalism.” This position maintains that, while teleological considerations can underwrite a broad understanding of representation, the content of visual representation can only be determined empirically according (...) to accumulated past experience. A corollary is that a longstanding problem concerning the indeterminacy of visual content is dissolved. (shrink)

In 'Fodor's Modal Argument' I claim that Fodor's latest defence of narrow content does not work. I claim that Fodor's modal argument is an unsuccessful resurrection of the Logical Connection Argument. Russow claims that my arguments fail because I confuse cause properties with causal powers, focus on events rather than properties, and overlook the fact that Fodor is trying only to explain narrow behavior. In this paper, I plead 'not guilty' to all of Fodor's charges. Narrow content still does not (...) exist. (shrink)

The creative aspect of language use provides a set of phenomena that a science of language must explain. It is the “central fact to which any signi- ficant linguistic theory must address itself” and thus “a theory of language that neglects this ‘creative’ aspect is of only marginal interest” (Chomsky 1964: 7–8). Therefore, the form and explanatory depth of linguistic science is restricted in accordance with this aspect of language. In this paper, the implications of the creative aspect of language (...) use for a scientific theory of language will be discussed, noting the possible further implications for a science of the mind. It will be argued that a corollary of the creative aspect of language use is that a science of language can study the mechanisms that make language use possible, but that such a science cannot explain how these mechanisms enter into human action in the form of language use. (shrink)

This piece criticizes Fodor's argument (in The Elm and the Expert, 1994) for the claim that Frege cases should be treated as exceptions to (broad) psychological generalizations rather than as counterexamples.

M any philosophers who otherwise have disparate views on the mind share a fundamental assumption. The assumption is that mental processes, or at least those that explain behavior, are wholly determined by properties of the individual whose processes they are.' As elaborated by..

This is a response to three critical discussions of my book Memory: A Philosophical Study (Oxford University Press 2010): Marya Schechtman, Memory and Identity , Fred Adams, Husker Du? , and Sanford Goldberg The Metasemantics of Memory.