Philosophy of Mind

Fodor

Since the beginning of his career in the early 1960's Jerry Fodor has been able to produce a number of discrete arguments regarding cognitive science and philosophy of the mind; and just as these two fields of thought are distinct yet similar, so too are Fodor's major theses. In 1983 Fodor published his book Modularity of the Mind and argued that many low-level, peripheral systems of the mind are modular. In 1987 his Psychosemantics was published, and within it he made a strong case for the causal theory of reference. Though superficially unrelated, after analyzing Fodor's works it becomes evident that his particular form of causal reference grows out of his case for modularity. "What binds together the various elements of Fodor's output is that they all count as engagements in a single project." (Cain, 1). Fundamentally, Fodor's approach to the mind is tempered with his commitments to physicalism and folk psychology; from these two core notions do all of his most radial ideas stem. In fact, spanning this conceptual bridge is what allows Fodor to span philosophy of the mind and cognitive science so compellingly. However, it is not altogether obvious that modularity necessarily demands a causal theory of reference; conceptual role semantics may also be congruous with certain understandings of modularity. So although Fodor's lines of reasoning tend to mutually reinforce one another, it is centrally his leap between physicalism and folk psychology that makes the leap between modularity of the mind and the causal theory of reference.

Fodor's unique devotions to folk psychology and physicalism have allowed his career and writings to last decades because in weaving them together, he has managed to take a traditional, holistic approach to the mind and link it to an empirical philosophical concept. Generally, "The theory of folk psychology purports that our mental states can, in some way, be interpreted in terms of beliefs and desires and that these beliefs and desires can be learned by observing behavior." (McKinlay 1999). This is simply the kind of psychology that everyone tends to engage in on an everyday basis. From observing those around you -- what they say, and how they behave in certain situations -- it is possible to predict and understand their behavior based upon your own mental states and the mental states you perceive others to experience. Folk psychology tends to emphasize intentional states of mind; like beliefs, desires, intentions, expectations, hopes, and fears. These intentional states additionally factor prominently in causal theories of the mind. Environmental factors can cause intentional states of mind. Furthermore, intentional states can also be the cause of other intentional states. Finally, intentional states of mind can directly cause behavior. The apparent advantage of folk psychology in this respect is that it holds the capacity to make broad generalizations about how states of mind interact with each other and the environment based upon common sense. "Hence, there exists a large battery of counterfactual and hypothetical supporting generalizations relating intentional states to one another, to environmental impingements and to behavior." (Cain, 4).

The generalizations regarding states of mind, which people make day-to-day, are significant because their accuracy suggests that most behaviors are the end result of mini-valid lines of reasoning worked through in each individual's mind. For instance, if I hold the belief that anyone at my door with a clipboard is trying to sell me something, and I also know that I have no money, the behavior of not answering the door when an individual with a clipboard appears is readily explained. Accordingly, it is possible for me to express these two mental states to an observer, and subsequently, they would be able to understand my behavior -- if not predict it. Fodor writes, "This parallelism between causal powers and contents engenders what is, surely, one of the most striking facts about the cognitive mind as commonsense belief/desire psychology conceives it: the frequent similarity between trains of thought and arguments." (Fodor 1987, 13). But despite the valid nature of the lines of reasoning human beings construct around intentional states, these arguments cannot invariably be sound. People's beliefs, hopes, and fears may -- and generally are -- based upon insufficient evidence, and accordingly, will vary from person to person depending upon their particular relationship to the external world. This does not eliminate the fact, however, that the major mechanisms by which people arrive at mental states are extremely analogous.

Fodor argues that the reason such a common understanding of the human thought process is applicable is the same reason that certain core scientific theories are accurate (Fodor 1987, 16). The reason this must be true is that scientific theories are merely specific collections of sentences, arranged in a way such that they are readily accepted as valid by nearly all who grasp their meanings. Additionally, since these scientific theories can be applied to the external world, it should not be surprising that general understandings of mental processes can be applied to other individuals. Essentially, observable phenomena in science translate into observable mental states in folk psychology. The accuracy of the core notions of science may be lessened in particular situations, but this does not devalue the core notions; instead, the inaccuracies must be described as variants of the original notion with respect to unique circumstances. Kepler's laws of planetary motion may not be accurate when describing the binding forces of the atom, but this is not because they are wrong and it is not because the forces described are not present: gravity is present in the atom, but its role in describing it is negligible. Consequently, specific instances in which intentional mental states play little or no role in determining human behavior could be devised, but they must be special cases of the underlying themes regarding folk psychology.

Finally, Fodor's form of folk psychology takes into account the realization that people in general cannot have a conscious grasp of exactly the kind of psychology they are engaging in. In other words, people are capable of understanding each other's behavior without being explicitly familiar with the mechanisms they employ to reach that understanding. This anomaly has its analogy in language: most speakers of the English language are able to speak it fluently and grammatically correct without having any formal understanding of its grammatical laws (Cain, 8). "Chomsky has famously argued that the best explanation of such capacities is that speakers of natural languages have a form of unconscious knowledge of the grammar of the language that they speak. Such unconscious knowledge is known as tacit knowledge and is held to be encoded in the brain." (Cain, 8). Recognizing this idea suggests that humans perform a similar sort of computation when making psychological inferences: we understand the causal laws that bind people's intentional states together, and we apply this knowledge without consciously knowing what we are doing.

Overall, Fodor's position regarding folk psychology -- commonsense psychology -- is that its value is evidenced by its accuracy in such an abundance of ordinary situations. However, for such a theory to be meaningful, the intentional states must exist in some physical reality, and they must be in reference to physical objects or ideas:

According to Jerry Fodor, if I believe a, then the representational content of the belief is a, no more than a sentence. Intentional mental states are therefore relations to sentences that organisms stand in. We can only understand intentional states if we accept that beliefs and desires are real, and that they represent intentional mental states in the form of sentences in what Fodor called the language of thought." (Chance 2005).

This interpretation of Fodor's writing illustrates his other major perspective with reference to cognitive science and philosophy of the mind: physicalism. "In a nutshell, physicalism is the doctrine that reality is ultimately physical in nature so that the sum totality of physical facts determines the sum totality of facts." (Cain, 10). This is a rather bold statement without some justifications. From Fodor's point-of-view, it is plausible that a physical description of everything -- the mind in particular -- might be accurate because the most general descriptions of the other branches of science can be put into physical terms. Chemistry, for example, is able to characterize the processes of photosynthesis or the replication of DNA on an atomic scale, but physics can describe the underlying forces that spur such processes and govern their outcomes. The same is true with the biological sciences, meteorological sciences, and geological sciences: they can all be reduced in terms of physics. Additionally, these disciplines tend to have generated the soundest scientific knowledge that human beings have yet acquired; this suggests, that strong adherences to our conception of physics -- consequently, the physical world -- hold the greatest possibility for the acquisition of factual information.

Fodor uses this observation to draw physics outside of the scientific realm and apply it to reality in general. Not only does Fodor endorse the idea that all of the sciences are subsets of physics, but that the entire universe can, and should, be described in physical terms. This sort of outlook fits well into Fodor's driving point regarding psychology: human behaviors can be understood as valid arguments relating intentional states of mind. In physics, when observable phenomena disagree with our understanding of the rules governing the physical world, it is not assumed that some other mystical force is at work -- merely that our observations or concepts concerning physics must somehow be mistaken in that specific situation. Furthermore, it is not assumed that we cannot know what caused the disparity between prediction and observation -- merely that it requires further inquiry. Similarly, Fodor does not assert that the workings of the mind cannot be understood because we may be unable to directly observe them, nor does he contend that something nonphysical is at work when disagreements occur. Fodor's physicalism approaches the mind from the perspective that the mind is a complex physical system, and that mental states must, accordingly, be physical properties of an individual's mind.

The most obvious difficulty with this sort of approach to the mind is that the relationship between the physical world and an equally physical interpretation of it in the mind is not altogether apparent. If reality is the complete sum of physical objects, it is hard to imagine how a physical mind could be capable of possessing an infinite number of physical bits of information and also rely upon rational thought processes (Cain, 16). Much of Fodor's philosophy can be seen as a response to this age-old dilemma. He seeks to deliberately place folk psychology within his overall physicalist framework in order to justify the former and provide a guide to how a better functioning form of cognitive science might be approached. Since he embraces both physicalism and folk psychology, Fodor is faced with the task of explaining why our subliminal understandings of psychology should be accurate within the physical world. Problems arise with this model of the mind when modularity is reconciled with causal reference. Fodor brings these two notions together as a result of his competing psychological and philosophical pulls, but the consequences are somewhat dubious.

Despite his firm belief in commonsense psychology, Fodor takes a drastic step out of it when he issues his support for modularity within Modularity of the Mind. He writes, "Behavior is organized, but the organization of behavior is merely derivative; the structure of behavior stands to mental structure as an effect stands to its cause." (Fodor 1983, 2). With this statement he illustrates his affiliation with folk psychology in that he draws a connection between observable behavior and perceived mental causes of that behavior. However, his reverence for physicalism means that his next question demands a sufficient answer: "But whereof does the structure of the mind consist?" (Fodor 1983, 2). Because of this question, Fodor is forced to engage in a discussion regarding the possible architectures that could make up the human mind. He regards the mind as not a single entity that tallies and organizes information throughout its structure, but as one composed of different systems that are related but discrete. Superficially -- from the folk psychology perspective -- the mind may seem to act as a single system, but Fodor cannot embrace this notion because the mind must be bounded.

In general, "There are two dimensions along which distinct modularity theses may differ. First, they may differ with respect to the account of the nature of mental modules that they incorporate.... Second, they may differ with respect to their account of the number and identity of the mental modules in the human mind." (Cain, 184). In other words, advocates of modularity in the human mind routinely disagree over specifically what a module is, and how many of them occur in the mind. Accordingly, it is essential to place Fodor somewhere within this spectrum: he believes that modules are entirely specific to the tasks they perform, and that the human mind holds at least six of them. But in order to keep his conception of folk psychology sound, he also recognizes that many of the observable human behaviors come from a functioning of the mind that is not modular: "High-level perception and cognitive systems are non-modular on Fodor's theory." (Prinz 2005). Nevertheless, Fodor justifies modularity in such a way that it can be applied to more extreme versions of the theory.

Modularity -- to most philosophers of the mind -- is a more strict and controversial extension of functional decomposition. This is the idea that the mind contains systems that are defined by the particular functions that they carry out. The essential claims of modularity refer to what these systems might be like, how they might operate, and how they might relate to one another. Fodor's individual brand of modularity is characterized by nine properties: (1) they are localized with respect to the brain; (2) they are subject to characteristic breakdowns; (3) they operate in an automatic manner; (4) they perform their duties quickly; (5) they have simple output functions; (6) they develop in a particular order and speed; (7) they operate within a set framework of inputs; (8) they are inaccessible to the higher level systems of the mind; and (9) they cannot be influenced by the higher levels of the mind (Fodor 1983, 47-100). He explains, "The modularity of the input systems consists of their possession of most or all of the properties now... enumerated. If there are other psychological systems which possess most or all of these properties then, of course, they are modular too." (Fodor 1983, 47). This is a rather strange assertion because Fodor does not make it clear exactly what his list of nine criteria is intended to accomplish. The words "most or all" suggest that if a mental system satisfies five of the criteria then it is a module; however, it is not obvious why this should be true. One critic has wondered, "Perhaps a system is modular to the extent that it exhibits properties on the list. Alternatively, some of the properties may be essential, while others are merely diagnostic." (Prinz 2005). In short, the list itself is questionable in its organization and function; so too are several of its portions.

Fodor's first and most powerful premise is that the brain exhibits localized functions. He points to a handful of experiments which indicate that this may be the case with reference to certain forms of input and response. Color perception, analysis of shapes and regions all display evidence of being regionally organized within the brain; yet, despite indications of some consistency concerning these possible modules, many independent studies have concluded that sight perceptions have been identified as being located in many regions across the brain (Cain 87). Nevertheless, Fodor uses this premise to assert, "Since the satisfaction of the universals is supposed to be a property that distinguishes sentences from other stimulus domains, the more elaborate and complex the theory of universals comes to be the more eccentric the stimulus domain for sentence recognition." (Fodor 1983, 51). From this, he concludes that this eccentricity can only be accounted for by inputs from multiple modular systems. Accordingly, he rejects the idea that a mechanism used for facial recognition, for example, could ever be involved in the sentence recognition which must occur elsewhere.

The major trouble with this premise is that the level of localization of brain functions that has been observed in the lab does not adequately support the strong levels of localization that would back modularity. "Evidence for strong localization is difficult to come by. Similar brain areas are active during multiple tasks, and focal brain lesions tend to produce multiple deficits." (Prinz 2005). The unanswered question, to Fodor, is how the unspecific nature of the input domain results in the specialization of the metal mechanisms at work. He leaves this objection relatively open, but is optimistic that localization holds-up irrespective of the manner by which information is received.

Fodor also agues that modules are mandatory, fast, and shallow. Essentially, some mental processes are not mandatory, in that we can choose whether or not to do them; but to Fodor, modules exhibit the characteristic that we cannot choose whether or not to do them. "For example, if you hear a sentence of a language that you know then you cannot help but hear it as a sentence; you do not have the power to 'switch off' the processes that result in your hearing it as a sentence as opposed to a pure sound." (Cain, 186). Yet, although we may automatically recognize colors, objects, or words, we retain the capacity to manipulate them as we see fit. We can devise any sentence we want, imagine any assortment of colors we want, or organize objects in our mind however we want. Certainly this ability must be related to our knack for recognizing these things quickly and without deliberation, but this is not addressed by Fodor.

Furthermore, quickness -- in itself -- truly implies nothing concerning modularity. In truth, virtually every function a module could carry out will be carried out at differing rates depending upon the details of the situation. Let us suppose you claim that a module exists for writing the English language with pencil and paper. Certainly, this is a learned characteristic, which required practice for your mind to obtain and master the transference of words onto a page. Someone might propose that this is an entirely discrete system concerned only with this single process, which may become automatic through time -- like speech. However, what if this same person began to learn how to draw? Doubtlessly, they would be using some of the same -- now automatic -- processes they use for writing, but they would also need to borrow from notions of space and light. Additionally, it is conceivable that this person may become quite apt at drawing and this process too could become automatic. Next, they could take up painting and so on. With each further step their speed would be slow, but gradually increase. Also, each "automatic" process would depend upon other bits of information from the brain. In short, there is little indication that this trend is strictly limited to behavioral examples, or that the ability to write, draw or paint is limited to distinct modules or locals. Obviously, this example lies outside of Fodor's criteria because the output is not shallow, and the individual must consciously choose to write or draw; however, it illustrates the general mental inclination to use varying bits of knowledge to create a process that eventually becomes easy. Similarly, understanding words depends upon experience with any particular word, and this influences speed.

He writes that fast processes "contrast with the relative slowness of paradigmatic central processes like problem-solving; and... It is presumably no accident that these very fast psychological processes are mandatory." (Fodor 1983, 63). But distinctions along the lines of speed seem utterly arbitrary. It may take someone unfamiliar with trigonometry fifteen minutes to figure out what sin (?/2) is, but someone with more experience could not look at the problem without involuntarily thinking of zero. Though certainly an aspect of problem solving, such processes can be mandatory and can be exceedingly fast. So, this spectrum is applicable to any mental capacity; thus, these criteria for modularity are truly inconsequential.

In the same way, it is difficult to argue that modules will develop in the same order or way since they are entirely dependent upon experience. Still, "Fodor hypothesizes that input systems and the capacities associated with them develop at a rate and in an order that is uniform across the human species." (Cain, 189). but, just as someone may read sin (?/2) as complete gibberish and another person may read it as zero, the same could be said -- hypothetically -- of someone who lived in a world without blue and another person who involuntarily recognized it as the color of the sky. Therefore, it could not be predicted how modules -- if they exist -- might form in an individual, going only from the presumption that the mind in question belongs to a human being possessing all of his senses. This premise, put forward by Fodor, is truly a supposition of similar environments and not of similar mental systems.

Despite these objections to Fodor's criteria for modularity in certain mental systems, he sees modularity as an essential consequence of the function of perception. His point is that human perception, though evolutionary history, has endowed us with a distinct advantage in that it allows us to obtain empirical truths (Fodor 1989). The higher levels of perception, to Fodor, depend upon modular systems because they are fast and accurate sources of physical information; this information, in turn, can be used to formulate beliefs and make decisions regarding behavior. If the lower-level systems were not modular, then the conclusions they arrived at would reach the higher-levels of perception more slowly and be tarnished with aspects of beliefs, desires, and expectations. Modularity, to Fodor, is plausible because it is how organisms are able to utilize objective -- or somewhat objective -- information about the physical world. Since the world is physical, objectivity and adherence to the scientific method are the most valuable inputs an organism can have access to.

Fodor justifies his designations by identifying instances in which psychological processes cut across domains; in other words, he attempts illustrate that specific domains of thought can dissociate from general intelligence in human beings. He recognizes that, "Even if input systems are domain specific, there must be some cognitive mechanisms that are not.... So, again, the moral seems to be that there must be some mechanisms which cross the domains that input systems establish." (Fodor 1983, 101-3). There are numerous examples which tend to lend credence to this notion. "A case of individuals who suffer from an impairment of their linguistic capacities despite being of normal intelligence is constituted by a genetic disorder known as Specific Language Impairment." (Cain, 193). William's syndrome is another case in which individuals exemplify dissociation: they suffer from severe cognitive impairments, and yet, they function normally linguistically (Karmiloff-Smith 1995).

These cases offer specious support to Fodor's form of modularity. Although it is generally accepted that there are specific systems within the brain, there is little to suggest that the sort of rigid architecture demanded by modularity is the root of dissociation. Fodor disagrees: "My point is that this asymmetry, too, is likely no accident. Deductive logic is the theory of validity, and validity is a local property of sentences." (Fodor 1983, 128). Skills, in general, are married to locals and these locals do little more than contribute the most objective information to the overall processing entity as is possible within the limitations of the human mind.

Fodor does not, however, make the grand assertion that all mental capacities are modular in nature. He seems to find it self-evident that the broad decision-making processes of the mind are able to sort through a wide variety of information that the modules provide it access to; accordingly, it had no specific location or algorithmic function. "For example, the process of fixing perceptual beliefs involves integrating data from various input modules and generating beliefs that square with the subject's general beliefs about the world." (Cain, 194). Therefore, the human mind's confirmation mechanism -- concerning beliefs -- is isotropic. From this understanding Fodor returns to his central notion that the world is entirely physical; he recognizes that "the facts relevant to the confirmation of scientific hypotheses my be drawn from anywhere in the field of previously established empirical (or, of course) demonstrative truths." (Fodor 1983, 105). With reference to the mind, this is significant because it establishes his entire conception of the physical world -- including the physical mind -- as being an interconnected causal system in which events in one subset of the system can cause significant ramifications in the other (Cain, 195). So, the floating property of the higher levels of thought makes this causal relationship possible, and vindicates the idea that external physical events and objects can be directly related to mental phenomena.

Thus, Fodor accepts that scientific beliefs may be altered, no matter what they are, to complement any observable events; scientists, no matter how impartial, inevitably infuse their findings with presumptions, expectations, and beliefs. Scientists are able to alter their positions concerning any number of issues minimally in the face of apparent refutations. Accordingly the central workings of the mind, although physical, cannot be tied down to a single location or a single process. Since science is fundamentally limited by the physical number of experiments that can be run and the individual beliefs of the scientists, there tends to be a general inclination to more readily accept the most basic and elegant scientific theories as scientific facts. Similarly, the most basic theory of human psychology is that which we perform automatically: commonsense psychology.

This is where Fodor picks up his discussion in Psychosemantics. From the strongly physicalist nature of the previous work, Fodor expands on his brief endorsement of folk psychology and attempts to generate an argument that can both accept the notion and demonstrate that mental states are physical states as well. "We have no reason to doubt," Fodor says, "that it is possible to have a scientific psychology that vindicates commonsense belief/desire explanation." (Fodor 1987, 16). He explains his particular version of the Representational Theory of the Mind -- RTM -- in which he claims there are "entities which -- like the attitudes -- are both semantically evaluable and etiologically involved." (Fodor 1987, 26).

Fodor's view is that the mental representations pertaining to certain physical objects or entities denote those objects because there is a causal link between the objects and the mental representation of it. Naturally, this link is subject to the presence of a particular object in a person's environment. Put differently, "instances of the mental representation underlying the word dog denote dogs because the former are under the causal control of instances of dogs in the environment." (UVA 2004). So the meaning of different physical objects in the physical world is pulled through the mental world by virtue of their presence. Fodor recognizes that the acts of speech an individual exhibits are not directly related to the environment in which he is placed -- thoughts, therefore, possess a far closer relationship with the physical than does verbal language.

Additionally, Fodor argues that if psychology is going to deal with issues of determinant content, then it is forced to abide by the idea that "extension constrains content." (Dennett 1988). In keeping with his commonsense psychology, he also contends that psychology must adhere as closely to the scientific method as possible; this includes discarding the "black box" model of the mind, and the implementation of the idea that the mind is comprised of physical matter which can be understood in physical terms. Daniel C. Dennett notes,

The only way to meet both conditions at once is to distinguish notions of narrow and broad content. Narrow content is supervenient on the organism's internal, causal states, and broad content is then held to be a function of narrow content relativized to environmental context. Plunking an organism into different contexts while holding its brain constant cannot change its narrow content, but can in principle alter the broad content of its psychological states." (Dennett 1988).

Basically, the mental states of an organism are bounded by a finite amount of information interpreted from a broad amount of external inputs. Along these lines Fodor is attempting to make psychology naturalistic in the way that the other sciences -- with more evident links to physics -- appear. Fodor, accordingly, attacks the idea that an individual's conception of any idea is dependent upon the whole of the beliefs taken up by that individual over the course of their lives which they still retain; he calls this Meaning Holism, or MH. Fundamentally,

Meaning Holism (MH) is the thesis that what a linguistic expression means depends on its relations to many or all other expressions within the same totality. Sometimes these relations are called 'conceptual' or 'inferential'. A related idea is that what an expression means depends, mutually, on the meaning of the other expressions in the totality, or alternatively on some semantic property of this totality itself." (Pagin 2005).

To Fodor, this is a "really is a crazy doctrine." (Fodor 1987, 60). After lying to waste Meaning Holism and its subsequent backings, "The task then falls to him, in the last chapter, to make good on this by defining in non-semantic, non-functional, non- teleological terms the conditions under which a mental representation expresses a property. In the end, after successive elaborations and improvements, we are offered the Slightly Less Crude Causal Theory of Content." (Dennett 1988).