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Generally, those who, like informational theorists, think relations to one's (natural or social) environment are (at least partially) determinative of the content of mental representations are Externalists, whereas of those who, like some proponents of functional theories, think contentually representative, if only to be determined by an individual's intrinsic properties alone, are internalists (or individualists).


This issue is widely taken to be of central importance, since psychological explanation, whether commonsense or scientific, is supposed to be both causal and content-based. (Beliefs and desires cause the behaviours they do because they have the contents they do. For example, the desire that one have a beer and the beliefs that there is beer in the refrigerator and that the refrigerator is in the kitchen may explain one's getting up and going to the kitchen.) If, however, a mental representation's having a particular content is due to factors extrinsic to it, it is unclear how its having that content could determine its causal powers, which, arguably, must be intrinsic. Some who accept the standard arguments for externalism have argued that internal factors determine a component of the content of a mental representation. They say that mental representations have both 'narrow' content (determined by intrinsic factors) and 'wide' or 'broad' content (determined by narrow content plus extrinsic factors). (This distinction may be applied to the sub-personal representations of cognitive science as well as to those of commonsense psychology.

Narrow content has been variously construed. Putnam (1975), Fodor (1982)), and Block (1986), for example, seem to understand it as something like de dicto content (i.e., Frégean sense, or perhaps character, à la Kaplan 1989). On this construal, narrow content is context-independent and directly expressible. Fodor (1987) and Block (1986), however, have also characterized narrow content as radically inexpressible. On this construal, narrow content is a kind of proto-content, or content-determinant, and can be specified only indirectly, via specifications of context/wide-content pairings. On both construal, narrow contents are characterized as functions from context to (wide) content. The narrow content of a representation is determined by properties intrinsic to it or its possessor such as its syntactic structure or its intra-mental computational or inferential role (or its phenomenology.

Burge (1986) has argued that causation-based worries about externalist individuation of psychological content, and the introduction of the narrow notion, are misguided. Fodor (1994, 1998) has more recently urged that of a familiarization for adjusting to an orderly scientific  psychological, however, this might not need narrow content in order to supply naturalistic (causal) explanations of human cognition and action, since the sorts of cases they were introduced to handle, viz., Twin-Earth cases and Frége cases, are nomologically either impossible or dismissible as exceptions to non-rigid and less of a sternful psychological law.

The leading contemporary version of the Representational Theory of Mind, the Computational Theory of Mind, claims that the brain is a kind of computer and that mental processes are computations. According to the computational theory of mind, cognitive states are constituted by computational relations to mental representations of various kinds, and cognitive processes are sequences of such states. The computational theory of mind and the representational theory of mind, may by attempting to explain all psychological states and processes in terms of mental representation. In the course of constructing detailed empirical theories of human and animal cognition and developing models of cognitive processes' implementable in artificial information processing systems, cognitive scientists have proposed a variety of types of mental representations. While some of these may be suited to be mental relata of commonsense psychological states, some - so-called 'subpersonal' or 'sub-doxastic' representations - are not. Though many philosophers believe that computational theory of mind can provide the best scientific explanations of cognition and behaviour, there is disagreement over whether such explanations will vindicate the commonsense psychological explanations of prescientific representational theory of mind.

According to Stich's (1983) Syntactic Theory of Mind, for example, computational theories of psychological states should concern themselves only with the formal properties of the objects those states are relations to. Commitment to the explanatory relevance of content, however, is for most cognitive scientists fundamental (Fodor 1981, Pylyshyn 1984, Von Eckardt 1993). That mental processes are computations, which computations are rule-governed sequences of semantically evaluable objects, and that the rules apply to the symbols in virtue of their content, are central tenets of mainstream cognitive science.

Explanations in cognitive science appeal to a many different kinds of mental representation, including, for example, the 'mental models' of Johnson-Laird 1983, the 'retinal arrays,' 'primal sketches' and '2½ -Dimensional sketches' of Marr, 1982 'frames' of Minsky 1974, the 'sub-symbolic' structures of Smolensky 1989, the 'quasi-pictures' of Kosslyn 1980, and the 'interpreted symbol-filled arrays' of Tye 1991 - in addition to representations that may be appropriate to the explanation of commonsense psychological states. Computational explanations have been offered of, among other mental phenomena, belief (Fodor 1975, Field 1978), visual perception (Marr 1982, Osherson, et al. 1990), rationality (Newell and Simon 1972, Fodor 1975, Johnson-Laird and Wason 1977), language learning and  (Chomsky 1965, Pinker 1989), and musical comprehension (Lerdahl and Jackendoff 1983).

A fundamental disagreement among proponents of computational theory of mind concerns the realization of personal-level representations (e.g., thoughts) and processes (e.g., inferences) in the brain. The central debate here is between proponents of Classical Architectures and proponents of Conceptionist Architectures.