Jerry A. Fodor

Connectionism and cognitive architecture: a critical analysis

Abstract This paper explores differences between Connectionist proposals for cognitive architecture and the sorts of models that have traditionally been assumed in cognitive science. We claim that the major distinction is that, while both Connectionist and Classical architectures postulate representational mental states, the latter but not the former are committed to a symbol-level of representation, or to a ‘language of thought’: i.e., to representational states that have combinatorial syntactic and semantic structure. Several arguments for combinatorial structure in mental representations are then reviewed. These include arguments based on the ‘systematicity’ of mental representation: i.e., on the fact that cognitive capacities always exhibit certain symmetries, so that the ability to entertain a given thought implies the ability to entertain thoughts with semantically related contents. We claim that such arguments make a powerful case that mind/brain architecture is not Connectionist at the cognitive level. We then consider the possibility that Connectionism may provide an account of the neural (or ‘abstract neurological’) structures in which Classical cognitive architecture is implemented. We survey a number of the standard arguments that have been offered in favor of Connectionism, and conclude that they are coherent only on this interpretation.

The structure of a semantic theory

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. Linguistic Society of America is collaborating with JSTOR to digitize, preserve and extend access to Language. 1. Introduction. This paperl does not attempt to present a semantic theory of a natural language, but rather to characterize the form of such a theory. A semantic theory of a natural language is part of a linguistic description of that language. Our problem, on the other hand, is part of the general theory of language, fully on a par with the problem of characterizing the structure of grammars of natural languages. A characterization of the abstract form of a semantic theory is given by a metatheory which answers such questions as these: What is the domain of a semantic theory? What are the descriptive and explanatory goals of a semantic theory? What mechanisms are employed in pursuit of these goals? What are the empirical and methodological constraints upon a semantic theory? The present paper approaches the problem of characterizing the form of semantic theories by describing the structure of a semantic theory of English. There can be little doubt but that the results achieved will apply directly to semantic theories of languages closely related to English. The question of their applicability to semantic theories of more distant languages will be left for subsequent investigations to explore. Nevertheless, the present investigation will provide results that can be applied to semantic theories of languages unrelated to English and suggestions about how to proceed with the construction of such theories. We may put our problem this way: What form should a semantic theory of a natural language take to accommodate in the most revealing way the facts about the semantic structure of that language supplied by descriptive research? This question is of primary importance at the present stage of the development of semantics because semantics suffers not from a dearth of facts about meanings and meaning relations in natural languages, but rather from the lack of an adequate theory to organize, systematize, and generalize these facts. Facts about the semantics of natural languages have been contributed in abundance by many diverse fields, including philosophy, linguistics, philology, and …

Methodological solipsism considered as a research strategy in cognitive psychology

The paper explores the distinction between two doctrines, both of which inform theory construction in much of modern cognitive psychology: the representational theory of mind and the computational theory of mind. According to the former, propositional attitudes are to be construed as relations that organisms bear to mental representations. According to the latter, mental processes have access only to formal (nonsemantic) properties of the mental representations over which they are defined. The following claims are defended: (1) That the traditional dispute between “rational” and “naturalistic” psychology is plausibly viewed as an argument about the status of the computational theory of mind. Rational psychologists accept a formality condition on the specification of mental processes; naturalists do not. (2) That to accept the formality condition is to endorse a version of methodological solipsism. (3) That the acceptance of some such condition is warranted, at least for that part of psychology which concerns itself with theories of the mental causation of behavior. This is because: (4) such theories require nontransparent taxonomies of mental states; and (5) nontransparent taxonomies individuate mental states without reference to their semantic properties. Equivalently, (6) nontransparent taxonomies respect the way that the organism represents the object of its propositional attitudes to itself , and it is this representation which functions in the causation of behavior. The final section of the paper considers the prospect for a naturalistic psychology: one which defines its generalizations over relations between mental representations and their environmental causes, thus seeking to account for the semantic properties of propositional attitudes. Two related arguments are proposed, both leading to the conclusion that no such research strategy is likely to prove fruitful.

The psychological reality of linguistic segments

Experimentation with the subjective location of clicks heard during speech supports the following conclusions: (a) Clicks are attracted towards the nearest major syntactic boundaries in sentential material. (b) The number of correct responses is significantly higher in the case of clicks located at major segment boundaries than in the case of clicks located within segments. (c) These results are consistent with the view that the segments marked by formal constituent structure analysis in fact function as perceptual units and that the click displacement is an effect which insures the integrity of these units. (d) The distribution of acoustic pauses in the sentential material does not account for the observed distribution of errors. (e) There is a slight tendency to prepose responses to clicks in sentences. This tendency is reversed during later stages of the experimental session. Both these effects are asymmetrical for the two ears.

Some syntactic determinants of sentential complexity

The perceptual complexity of three lists of self-embedded sentences was evaluated in terms of the accuracy and time required for their paraphrase. The lists differed by the presence of relative pronouns in one list, their absence in a second and by the addition of adjectives to the third. It was predicted that the presence of the relative pronouns would effect the only significant change in performance. In both auditory and visual presentations of the sentence lists, the presence of the relative pronouns proved to be facilitating, while the presence of the adjectives produced no significant changes.

What psychological states are not

AS FAR as anyone knows, different organisms are often in psychological states of exactly the same type at one time or another, and a given organism is often in psychological states of exactly the same type at different times. Whenever either is the case, we shall say of the psychological states of the organism(s) in question that they are type identical. One thing that currently fashionable theories in the philosophy of mind often try to do is characterize the conditions for type identity of psychological states. For example, some varieties of philosophical behaviorism claim that two organisms are in typeidentical psychological states if and only if certain of their behaviors or behavioral dispositions are type identical. Analogously, some (though not all) varieties of physicalism claim that organisms are in type-identical psychological states if and only if certain of their physical states are type identical. In so far as they are construed as theories about the conditions for type identity of psychological states, it seems increasingly unlikely that either behaviorism or physicalism is true. Since

Semantic focus and sentence comprehension

Reaction time to detect a phoneme target in a sentence was found to be faster when the word in which the target occurred formed part of the semantic focus of the sentence. Focus was determined by asking a question before the sentence; that part of the sentence which comprised the answer to the sentence was assumed to be focussed. This procedure made it possible to vary position of focus within the sentence while holding all acoustic aspects of the sentence itself constant. It is argued that sentence understanding is facilitated by rapid identification of focussed information. Since focussed words are usually accented, it is further argued that the active search for accented words demonstrated in previous research should be interpreted as a search for semantic focus.

The active use of grammar in speech perception

Judgments of the location of short bursts of noise in sentences were used to reveal perceptual segmentation of sentences. It was assumed that segmentation would correspond to major constituent boundaries. In order to control for correlated variables of pitch and intonation, identical acoustic material was provided with alternate constituent structures. It was found that differences in response to identical strings were predicted by the points of variation in constituent structure.

Tom Swift and his procedural grandmother

Rumor has it that, in semantics, AI is where the action is. We hear not only that computational (hereafter ‘procedural’) semantics offers an alternative to the classical semantics of truth, reference and modality’, but that it provides what its predecessor so notably lacked: clear implications for psychological models of the speaker/hearer. Procedural semantics is said to be ‘the psychologist’s’ theory of meaning, just as classical semantics was ‘the logician’s’. What’s bruited in the by-ways is thus nothing less than a synthesis of the theory of meaning with the theory of mind. Glad tidings these, and widely credited. But, alas, unreliable. I shall argue that, soberly considered: (a) The computer models provide no semantic theory at all, if what you mean by a semantic theory is an account of the relation between language and the world. In particular, procedural semantics doesn’t supplant classical semantics, it merely begs the questions that classical semanticists set out to answer. The begging of these questions is, of course, quite inadvertent; we shall consider at length how it comes about. (b) Procedural semantics does provide a theory about what it is to know the meaning of a word. But it’s not a brave new theory. On the contrary, it’s just an archaic and wildly implausible form of verificationism. Since practically nobody except procedural semanticists takes verificationism seriously any more, it will be of some interest to trace the sources of their adherence to the doctrine. (c) It’s the verificationism which connects the procedural theory of language to the procedural theory of perception. The consequence is a view of the relation between language and mind which is not significantly different from that of Locke or Hume. The recidivism of PS theorizing is among the most striking of the ironies now to be explored.

Some syntactic determinants of sentential complexity, II : Verb structure

The effect of the lexical complexity of verbs on the processing of sentences was evaluated in two experiments. Verb complexity was indexed by the number of types of grammatical structure a verb permits (e.g., a verb may be transitive or intransitive and may permit various types of complement structures). Ss’ performances in paraphrasing sentences and in solving anagrams containing complex verbs were significantly poorer than their performances with the same sentences and anagrams containing less complex verbs.