Presented by: Richard j.Kosciejew
Classicists are motivated (in part) by properties thought seems to share with language. Jerry Alan Fodor's (1935-), Language of Thought Hypothesis, (Fodor 1975, 1987), according to which the system of mental symbols constituting the neural basis of thought is structured like a language, provides a well-worked-out version of the classical approach as applied to commonsense psychology. According to the language of a thought hypothesis, the potential infinity of complex representational mental states is generated from a finite stock of primitive representational states, in accordance with recursive formation rules. This combinatorial structure accounts for the properties of productivity and systematicity of the system of mental representations. As in the case of symbolic languages, including natural languages (though Fodor does not suppose either that the language of thought hypotheses explains only linguistic capacities or that only verbal creatures have this sort of cognitive architecture), these properties of thought are explained by appeal to the content of the representational units and their combinability into contentful complexes. That is, the semantics of both language and thought is compositional: the content of a complex representation is determined by the contents of its constituents and their structural configuration.
Connectionists are motivated mainly by a consideration of the architecture of the brain, which apparently consists of layered networks of interconnected neurons. They argue that this sort of architecture is unsuited to carrying out classical serial computations. For one thing, processing in the brain is typically massively parallel. In addition, the elements whose manipulation drive's computation in Conceptionist networks (principally, the connections between nodes) are neither semantically compositional nor semantically evaluable, as they are on the classical approach. This contrast with classical computationalism is often characterized by saying that representation is, with respect to computation, distributed as opposed to local: representation is local if it is computationally basic; and distributed if it is not. (Another way of putting this is to say that for classicists mental representations are computationally atomic, whereas for connectionists they are not.)
Moreover, connectionists argue that information processing as it occurs in Conceptionist networks more closely resembles some features of actual human cognitive functioning. For example, whereas on the classical view learning involves something like hypothesis formation and testing (Fodor 1981), on the Conceptionist model it is a matter of evolving distribution of 'weight' (strength) on the connections between nodes, and typically does not involve the formulation of hypotheses regarding the identity conditions for the objects of knowledge. The Conceptionist network is 'trained up' by repeated exposure to the objects it is to learn to distinguish; and, though networks typically require many more exposures to the objects than do humans, this seems to model at least one feature of this type of human learning quite well.
Further, degradation in the performance of such networks in response to damage is gradual, not sudden as in the case of a classical information processor, and hence more accurately models the loss of human cognitive function as it typically occurs in response to brain damage. It is also sometimes claimed that Conceptionist systems show the kind of flexibility in response to novel situations typical of human cognition - situations in which classical systems are relatively 'brittle' or 'fragile.'
Some philosophers have maintained that Connectionism entails that there are no propositional attitudes. Ramsey, Stich and Garon (1990) have argued that if Conceptionist models of cognition are basically correct, then there are no discrete representational states as conceived in ordinary commonsense psychology and classical cognitive science. Others, however (e.g., Smolensky 1989), hold that certain types of higher-level patterns of activity in a neural network may be roughly identified with the representational states of commonsense psychology. Still others argue that language-of-thought style representation is both necessary in general and realizable within Conceptionist architectures, collect the central contemporary papers in the classicist/Conceptionist debate, and provides useful introductory material as well.
Whereas Stich (1983) accepts that mental processes are computational, but denies that computations are sequences of mental representations, others accept the notion of mental representation, but deny that computational theory of mind provides the correct account of mental states and processes.
Van Gelder (1995) denies that psychological processes are computational. He argues that cognitive systems are dynamic, and that cognitive states are not relations to mental symbols, but quantifiable states of a complex system consisting of (in the case of human beings) a nervous system, a body and the environment in which they are embedded. Cognitive processes are not rule-governed sequences of discrete symbolic states, but continuous, evolving total states of dynamic systems determined by continuous, simultaneous and mutually determining states of the systems components. Representation in a dynamic system is essentially information-theoretic, though the bearers of information are not symbols, but state variables or parameters.
Horst (1996), on the other hand, argues that though computational models may be useful in scientific psychology, they are of no help in achieving a philosophical understanding of the intentionality of commonsense mental states. Computational theory of mind attempts to reduce the intentionality of such states to the intentionality of the mental symbols they are relations to. But, Horst claims, the relevant notion of symbolic content is essentially bound up with the notions of convention and intention. So the computational theory of mind involves itself in a vicious circularity: the very properties that are supposed to be reduced are (tacitly) appealed to in the reduction.
To say that a mental object has semantic properties is, paradigmatically, to say that it may be about, or be true or false of, an object or objects, or that it may be true or false simpliciter. Suppose I think that you took to sniffing snuff. I am thinking about you, and if what I think of you (that they take snuff) is true of you, then my thought is true. According to representational theory of mind such states are to be explained as relations between agents and mental representations. To think that you take snuff is to token in some way a mental representation whose content is that ocelots take snuff. On this view, the semantic properties of mental states are the semantic properties of the representations they are relations to.
Linguistic acts seem to share such properties with mental states. Suppose I say that you take snuff. I am talking about you, and if what I say of you (that they take snuff) is true of them, then my utterance is true. Now, to say that you take snuff is (in part) to utter a sentence that means that you take snuff. Many philosophers have thought that the semantic properties of linguistic expressions are inherited from the intentional mental states they are conventionally used to express. On this view, the semantic properties of linguistic expressions are the semantic properties of the representations that are the mental relata of the states they are conventionally used to express.
It is also widely held that in addition to having such properties as reference, truth-conditions and truth - so-called extensional properties - expressions of natural languages also have intensional properties, in virtue of expressing properties or propositions - i.e., in virtue of having meanings or senses, where two expressions may have the same reference, truth-conditions or truth value, yet express different properties or propositions (Frége 1892/1997). If the semantic properties of natural-language expressions are inherited from the thoughts and concepts they express (or vice versa, or both), then an analogous distinction may be appropriate for mental representations.
Theories of representational content may be classified according to whether they are atomistic or holistic and according to whether they are externalistic or internalistic, whereby, emphasizing the priority of a whole over its parts. Furthermore, in the philosophy of language, this becomes the claim that the meaning of an individual word or sentence can only be understood in terms of its relation to an indefinitely larger body of language, such as whole theory, or even a whole language or form of life. In the philosophy of mind a mental state similarly may be identified only in terms of its relations with others. Moderate holism may allow the other things besides these relationships also count; extreme holism would hold that a network of relationships is all that we have. A holistic view of science holds that experience only confirms or disconfirms large bodies of doctrine, impinging at the edges, and leaving some leeway over the adjustment that it requires.
Once, again, in the philosophy of mind and language, the view that what is thought, or said, or experienced, is essentially dependent on aspects of the world external to the mind of the subject. The view goes beyond holding that such mental states are typically caused by external factors, to insist that they could not have existed as they now do without the subject being embedded in an external world of a certain kind. It is these external relations that make up the essence or identify of the mental state. Externalism is thus opposed to the Cartesian separation of the mental from the physical, since that holds that the mental could in principle exist as it does even if there were no external world at all. Various external factors have been advanced as ones on which mental content depends, including the usage of experts, the linguistic, norms of the community. And the general causal relationships of the subject. In the theory of knowledge, externalism is the view that a person might know something by being suitably situated with respect to it, without that relationship being in any sense within his purview. The person might, for example, be very reliable in some respect without believing that he is. The view allows that you can know without being justified in believing that you know.
However, atomistic theories take a representation's content to be something that can be specified independent entity of that representation' s relations to other representations. What the American philosopher of mind, Jerry Alan Fodor (1935-) calls the crude causal theory, for example, takes a representation to be a |cow| - menial representation with the same content as the word 'cow' - if its tokens are caused by instantiations of the property of being-a-cow, and this is a condition that places no explicit constraints on how |cow|'s must or might relate to other representations. Holistic theories contrasted with atomistic theories in taking the relations representation bears to others to be essential to its content. According to functional role theories, a representation is a |cow| if it behaves like a |cow| should behave in inference.
Internalist theories take the content of a representation to be a matter determined by factors internal to the system that uses it. Thus, what Block (1986) calls 'short-armed' functional role theories are Internalist. Externalist theories take the content of a representation to be determined, in part at least, by factors external to the system that uses it. Covariance theories, as well as telelogical theories that invoke an historical theory of functions, take content to be determined by 'external' factors. Crossing the atomist-holistic distinction with the Internalist-externalist distinction.
Externalist theories (sometimes called non-individualistic theories) have the consequence that molecule for molecule identical cognitive systems might yet harbour representations with different contents. This has given rise to a controversy concerning 'narrow' content. If we assume some form of externalist theory is correct, then content is, in the first instance 'wide' content, i.e., determined in part by factors external to the representing system. On the other hand, it seems clear that, on plausible assumptions about how to individuate psychological capacities, internally equivalent systems must have the same psychological capacities. Hence, it would appear that wide content cannot be relevant to characterizing psychological equivalence. Since cognitive science generally assumes that content is relevant to characterizing psychological equivalence, philosophers attracted to externalist theories of content have sometimes attempted to introduce 'narrow' content, i.e., an aspect or kind of content that is equivalent internally equivalent systems. The simplest such theory is Fodor's idea (1987) that narrow content is a function from contents (i.e., from whatever the external factors are) to wide contents.
All the same, what a person expresses by a sentence is often a function of the environment in which he or she is placed. For example, the disease I refer to by the term like 'arthritis', or the kind of tree I refer to as a 'Maple' will be defined by criteria of which I know next to nothing. This raises the possibility of imagining two persons in rather different environments, but in which everything appears the same to each of them. The wide content of their thoughts and sayings will be different if the situation surrounding them is appropriately different: 'Situation' may include the actual objects they perceive or the chemical or physical kinds of object in the world they inhabit, or the history of their words, or the decisions of authorities on what counts as an example, of one of the terms they use. The narrow content is that part of their thought which remains identical, through their identity of the way things appear, regardless of these differences of surroundings. Partisans of wide content may doubt whether any content in this sense narrow, partisans of narrow content believer that it is the fundamental notion, with wide content being explicable in terms of narrow content plus context.
Even so, the distinction between facts and values has outgrown its name: it applies not only to matters of fact vs, matters of value, but also to statements that something is, vs. statements that something ought to be. Roughly, factual statements - 'is statements' in the relevant sense - represent some state of affairs as obtaining, whereas normative statements - evaluative, and deontic ones - attribute goodness to something, or ascribe, to an agent, an obligation to act. Neither distinction is merely linguistic. Specifying a book's monetary value is making a factual statement, though it attributes a kind of value. 'That is a good book' expresses a value judgement though the term 'value' is absent (nor would 'valuable' be synonymous with 'good'). Similarly, 'we are morally obligated to fight' superficially expresses a statement, and 'By all indications it ough to rain' makes a kind of ought-claim; but the former is an ought-statement, the latter an (epistemic) is-statement.
Theoretical difficulties also beset the distinction. Some have absorbed values into facts holding that all value is instrumental, roughly, to have value is to contribute - in a factual analysable way - to something further which is (say) deemed desirable. Others have suffused facts with values, arguing that facts (and observations) are 'theory-impregnated' and contending that values are inescapable to theoretical choice. But while some philosophers doubt that fact/value distinctions can be sustained, there persists a sense of a deep difference between evaluating, and attributing an obligation and, on the other hand, saying how the world is.
Fact/value distinctions, may be defended by appeal to the notion of intrinsic value, as a thing has in itself and thus independently of its consequences. Roughly, a value statement (proper) is an ascription of intrinsic value, one to the effect that a thing is to some degree good in itself. This leaves open whether ought-statements are implicitly value statements, but even if they imply that something has intrinsic value - e.g., moral value - they can be independently characterized, say by appeal to rules that provide (justifying) reasons for action. One might also ground the fact value distinction in the attributional (or even motivational) component apparently implied by the making of evaluational or deontic judgements: Thus, 'it is a good book, but that is no reason for a positive attribute towards it' and 'you ought to do it, but there is no reason to' seem inadmissible, whereas, substituting, 'an expensive book' and 'you will do it' yields permissible judgements. One might also argue that factual judgements are the kind which are in principle appraisable scientifically, and thereby anchor the distinction on the factual side. This ligne is plausible, but there is controversy over whether scientific procedures are 'value-free' in the required way.
Philosophers differ regarding the sense, if any, in which epistemology is normative (roughly, valuational). But what precisely is at stake in this controversy is no clearly than the problematic fact/value distinction itself. Must epistemologists as such make judgements of value or epistemic responsibility? If epistemology is naturalizable, then even epistemic principles simply articulate under what conditions - say, appropriate perceptual stimulations - a belief is justified, or constitutes knowledge. Its standards of justification, then would be like standards of, e.g., resilience for bridges. It is not obvious, however, that there appropriate standards can be established without independent judgements that, say, a certain kind of evidence is good enough for justified belief (or knowledge). The most plausible view may be that justification is like intrinsic goodness, though it supervenes on natural properties, it cannot be analysed wholly in factual statements.
Thus far, belief has been depicted as being all-or-nothing, however, as a resulting causality for which we have grounds for thinking it true, and, all the same, its acceptance is governed by epistemic norms, and, least of mention, it is partially subject to voluntary control and has functional affinities to belief. Still, the notion of acceptance, like that of degrees of belief, merely extends the standard picture, and does not replace it.
Traditionally, belief has been of epistemological interest in its propositional guise: 'S' believes that 'p', where 'p' is a reposition towards which an agent, 'S' exhibits an attitude of acceptance. Not all belief is of this sort. If I trust you to say, I believer you. And someone may believe in Mr. Radek, or in a free-market economy, or in God. It is sometimes supposed that all belief is 'reducible' to propositional belief, belief-that. Thus, my believing you might be thought a matter of my believing, is, perhaps, that what you say is true, and your belief in free markets or God, is a matter of your believing that free-market economies are desirable or that God exists.
Some philosophers have followed St. Thomas Aquinas (1225-74), in supposing that to believer in God is simply to believer that certain truths hold while others argue that belief-in is a distinctive attitude, on that includes essentially an element of trust. More commonly, belief-in has been taken to involve a combination of propositional belief together with some further attitude.
The moral philosopher Richard Price (1723-91) defends the claim that there are different sorts of belief-in, some, but not all reducible to beliefs-that. If you believer in God, you believer that God exists, that God is good, you believer that God is good, etc. But according to Price, your belief involves, in addition, a certain complex pro-attitude toward its object. Even so, belief-in outruns the evidence for the corresponding belief-that. Does this diminish its rationality? If belief-in presupposes believes-that, it might be thought that the evidential standards for the former must be, at least, as high as standards for the latter. And any additional pro-attitude might be thought to require a further layer of justification not required for cases of belief-that.
Belief-in may be, in general, less susceptible to alternations in the face of unfavourable evidence than belief-that. A believer who encounters evidence against God's existence may remain unshaken in his belief, in part because the evidence does not bear on his pro-attitude. So long as this ids united with his belief that God exists, and reasonably so - in a way that an ordinary propositional belief that would not.
The correlative way of elaborating on the general objection to justificatory externalism challenges the sufficiency of the various externalist conditions by citing cases where those conditions are satisfied, but where the believers in question seem intuitively not to be justified. In this context, the most widely discussed examples have to do with possible occult cognitive capacities, like clairvoyance. Considering the point in application once, again, to reliabilism, the claim is that to think that he has such a cognitive power, and, perhaps, even good reasons to the contrary, is not rational or responsible and therefore not epistemically justified in accepting the belief that result from his clairvoyance, dispite the fact that the reliablist condition is satisfied.
One sort of response to this latter sorts of an objection is to 'bite the bullet' and insist that such believers are in fact justified, dismissing the seeming intuitions to the contrary as latent Internalist prejudice. A more widely adopted response attempts to impose additional conditions, usually of a roughly Internalist sort, which will rule out the offending example, while stopping far of a full internalism. But, while there is little doubt that such modified versions of externalism can handle particular cases, as well enough to avoid clear intuitive implausibility, the usually problematic cases that they cannot handle, and also whether there is and clear motivation for the additional requirements other than the general Internalist view of justification that externalist is committed to reject.
A view in this same general vein, one that might be described as a hybrid of internalism and externalism holds that epistemic justification requires that there is a justicatory factor that is cognitively accessible to the believer in question (though it need not be actually grasped), thus ruling out, e.g., a pure reliabilism. At the same time, however, though it must be objectively true that beliefs for which such a factor is available are likely to be true, in addition, the fact need not be in any way grasped or cognitively accessible to the believer. In effect, of the premises needed to argue that a particular belief is likely to be true, one must be accessible in a way that would satisfy at least weak internalism, the Internalist will respond that this hybrid view is of no help at all in meeting the objection and has no belief nor is it held in the rational, responsible way that justification intuitively seems to require, for the believer in question, lacking one crucial premise, still has no reason at all for thinking that his belief is likely to be true.
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