Posted by: Xhyra Graf | 29 January 2007

Teleology & Mental Content

Teleological theories of mental content try to explain the contents of mental representations by appealing to a teleological notion of function.

According to teleological theories of content, what a representation represents depends on the functions of the systems that use or (it depends on the version) produce the representation. The relevant notion of function is said to be the one that is used in biology and neurobiology in attributing functions to components of organisms (as in “the function of the pineal gland is releasing melatonin” and “the function of brain area MT is processing information about motion”). Proponents of teleological theories of content generally understand this notion to be the notion of what something was selected for, either by ordinary natural selection or by some other natural process of selection. Broad Aims

Teleological theories of content, like other theories of mental content, attempt to solve what is often referred to as Brentano’s problem: the problem of explaining how mental states can be about things or be directed on to things in this way.

One version of the problem, often attributed to Brentano but perhaps more correctly attributed to Roderick Chisholm (1957), concerns thoughts about non-existent objects. Chisholm argued that the aboutness (or intentionality) of mental states can not be a physical relation between a mental state and what it is about (its object) because in a physical relation each of the relata must exist whereas the objects of mental states might not exist.

Chisholm concluded that it is hard to see how intentionality can be a physical phenomenon, but those who offer teleological theories almost always adopt a physicalist framework to try to explain how intentionality is possible. They aim at what is often called a “naturalistic theory”: “naturalistic” because the aim is to give a theory that is consistent with the claim that the fundamental furniture of the universe is nothing but what the natural sciences describe. Within that framework, it is a working hypothesis that intentionality is not ontologically fundamental, so most teleological theories try to show that intentionality is part of the natural world by showing how it can be understood in terms of other natural things. In effect, those who propose teleological theories of mental content try to say why a mental representation, R, represents what it represents, C, by filling in the blank in, “R has the content C because (in virtue of) “, without making ineliminable use of intentional terms.

A theory of mental content will need to explain our capacity to represent non-existent things. Another thing it will need to explain is the normative nature of mental representation. Content is said to be normative because it legitimates certain evaluations. We evaluate beliefs as true or false, memories as accurate or inaccurate, perceptions as veridical or illusory, and so on.

Much attention is paid to the possibility of misrepresentation. This is because the distinction between correct and incorrect representation is often regarded as a central normative distinction and because a capacity to misrepresent is often thought to be essential for representing: no possibility of misrepresentation, no representing.

The word “content” has come to have some different uses in the philosophical literature. One important distinction is between referential content and something like cognitive role or mode of presentation. The teleological theories that are currently on offer are generally theories of referential content, not theories of cognitive role or mode of presentation.

Three remaining points about broad aims might be useful. One concerns what is known among philosophers as “narrow content”. By definition, narrow content supervenes on just the current, internal physical properties of the individual whose narrow-content state it is. Thus, two individuals who are physical replicas at a time, t, “from the skin in” must have the same narrow-content states at t. Proponents of teleological theories do not believe that regular normative content (that is, non-revisionary content) is narrow content.

A second further point about broad aims is that teleological theories of mental content are not generally intended as theories about how we grasp meanings or are conscious of them. To grasp a meaning is plausibly a sophisticated intentional state that involves representations of meanings and not just representations with meanings. To understand how we grasp meanings, we might turn to psychological theories of concept possession and introspective access to conceptual structures. Such theories presuppose that there are representations with content, whereas teleological theories of mental content try to explain the nature of intentionality at its most fundamental; they aim to say what it is to have representations with content.

Third, teleological theories of mental content are usually (although not always) intended as real nature theories. Those who offer real nature theories of intentionality are not trying to describe the criteria that we use in everyday life to identify the beliefs and desires of people. Those who offer teleological theories of mental content usually think that our everyday ability to recognize intentional states, such as beliefs and desires, does not make us experts about the fundamental nature of intentional states, any more than our everyday ability to recognize water makes us experts about the fundamental nature of water. Teleological Functions

As noted in the previous section, a crucial feature of content is that it legitimates semantic evaluations. While teleological theories of mental content come in a variety of forms, they all share the idea that the norms that underwrite these evaluations are derived, in part at least, from functions.

Intuitively, talk of functions in biology does seem to be teleological. Teleological contexts are ones in which there is reference to ends or goals, and relevant talk of functions seems to be teleological in this sense, because, for example, when we say that it is the function of the heart to pump blood, this seems equivalent to saying that hearts are for pumping blood or are there to pump blood.

Crucially, however, the relevant concept of function is not purposive. Purposes are intentional phenomena, so such a concept would not serve in a naturalistic theory of content if it were.

Some philosophers, including some proponents of what are usually known as teleological theories of content, would prefer to reserve the term “teleological” for purposive contexts. They prefer to refer to the biological concept of function as “teleonomic” instead. But, on a broad construal of what it means for a concept to be teleological, a concept is teleological if it concerns what something is for, and the notion of what something was selected for counts as teleological in that sense.

Intuitively, the relevant concept of function also seems to be normative, for biologists routinely talk about systems functioning normally or properly, as well as about abnormal functioning, malfunctioning, dysfunction, functional impairments, and so on. However, describing the term as “normative” is also controversial. Most would agree that the relevant notion of function is one that permits the possibility of malfunction.

The disagreement is about whether this suffices for the notion to count as normative, and the disagreement turns on a distinction between descriptive and prescriptive norms. Again, the disagreement is more terminological than substantial. Most (if not all) proponents of teleological theories think that functional norms are descriptive and not prescriptive, and the disagreement is over whether it is appropriate to refer to descriptive norms (or “norms”, if you prefer) as normative. Some prefer to reserve the term “normative” for prescriptive contexts, so that a statement would count as normative only if it entails an ought-claim without the addition of further premises. Perhaps most proponents of teleological theories of mental content would agree that no ought-claim follows from a simple function ascription, not at least without the addition of further premises (for discussion, see Jacob 2001).

The relevant notion of function, then, is thought to be teleological, in so far as it is the notion of what something is for, and normative, in so far as it permits the possibility of malfunction. Further, those who offer teleological theories of content favor an etiological theory of functions, according to which an item’s function is determined by its history of selection, or by past selection for things of that type. Larry Wright (1973, 1976) offered the first developed defense of an etiological theory, but earlier versions of the idea can also be found in the writings of some biologists (e.g., Ayala 1970). Wright’s proposed definition is as follows (Wright 1976, p. 81).

The function of X is Z if and only if,

  1. Z is a consequence (result) of Xs being there,
  2. X is there because it does (results in) Z.

Wright intended this formula to work for a wide variety of function ascriptions; for artifacts as well as the parts of organisms, and for functions that derive from intentional design as well as from natural selection, so that it would be applicable to Creationist as well as evolutionary biology. For this reason, he intended the “does” of the second requirement to be tenseless. Thus the second requirement is intended to be read as requiring that X be there because it does, did, or will do Z.

The details of this formula are generally regarded as problematic.

To play a role in a naturalistic account of mental content, the relevant selection process must be a natural process of selection, but it need not be ordinary genetic selection. Some have suggested that neural selection, conditioning and meme selection, could also ground content. However, it is not a trivial task to say what, in general, constitutes a selection process. Millikan (1984, chapter 1) offers an etiological theory that is not specific to physiological functions.

While etiological theories of function dominate the discussion of functions in philosophy of biology, this type of theory is not uncontroversial. Some question whether teleology can be naturalized (e.g., Bedau 1991), and others support other non-etiological and non-teleological accounts of biological function (e.g., Cummins 1975). Readers who would like to read more on this topic could turn to several volumes that have recently appeared: see especially Allen, Bekoff & Lauder 1998; Buller 1999; and Ariew, Cummins and Perlman 2002.

It is usual to note that etiological (teleological) functions are distinct from the causal-role functions involved in what is called “functionalism” in philosophy of mind. Causal-role functions are often defined as a select subset of a trait’s actual causal dispositions, and functionalism is often defined as the view that mental states are individuated or classified into types on the basis of such dispositions (see, e.g., Block 1984). If causal-role functions are a subset of dispositions actually possessed, they can not provide for the possibility of malfunction because a trait cannot have the causal-role function to D and at the same time lack the disposition to D.

Another reason teleological and classical functionalism are closer than might be thought is that, while teleological functions are often regarded as selected effects (i.e., effects of traits for which the traits were selected), they can also be regarded as selected dispositions (i.e., dispositions of traits for which the traits were selected). Of course, biological traits must have effects to be selected: traits must do something to enhance gene replication to be selected by genetic selection, for instance. But it is not just what, but also when, something is done that is crucial for selection, and one way to capture this fact is to acknowledge that traits are selected for dispositions to produce certain effects in response to certain causes. Teleological functions, like the functions of classical functionalism, can thus be seen as dispositions: not a select subset of currently possessed dispositions, but selected dispositions. Fucntional Indeterminancy

“The” functional indeterminacy problem (Dretske 1986; Fodor 1990b) is really at least two problems, or three, if we include the problem of distal content. Aside from the problem of distal content, which has been discussed above, there is the problem that natural selection is extensional and the problem of selection for complex causal roles. These are discussed in this section, starting with the problem that natural selection is extensional.

Fodor once devised a teleological theory of mental content (published years later, as Fodor 1990a). However, he quickly repudiated the idea and has since been one of the most vigorous critics of teleological theories. His main objection was that teleological theories leave content too indeterminate because functions are too indeterminate to determine content. Functional indeterminacy, according to Fodor (1990b), stems from the fact that natural selection is extensional in the following sense: if it is adaptive for an organism, O, to do something, M, in the presence of environmental feature, F, and F is reliably co-extensive with another feature, G, then it is equally adaptive for O to do M in the presence of G. Fodor argues that teleological theories therefore cannot distinguish between candidate contents that are co-extensional in the environment in which a creature evolved.

The content will then depend on how we choose to describe the function, and a content that depends on our choice is not a naturalized content.

The standard response to this objection starts by pointing out that the function of a trait is what that type of trait was selected for, and that the notion of selection for is a causal notion (Sterelny 1990; Millikan 1991). A trait is selected for its possession of a certain property only if that property causally contributed to its selection. Thus the pineal gland was selected for its releasing of melatonin only if the releasing of melatonin by ancestral pineal glands contributed to the preservation and proliferation of pineal glands in the population. Along similar lines, the heart was selected for circulating blood, but not for making a thumping noise, if the former but not the latter contributed to the selection of hearts. Functions can therefore distinguish between two properties that reliably co-vary as long as one but not the other caused the trait to be selected.

Fodor (1996) responds that there is anyway a remainder of a problem because content is more fine-grained than causation is. He points out that some pairs of properties are logically or nomologically co-extensive: e.g., being triangular and being trilateral, and being a renate and being a cordate. According to Fodor, since we cannot distinguish between selection for the one and selection for the other, there is a problem for teleological theories of content.

However, it is not obvious that this is a problem for a theory of referential content.

We turn now to the second functional indeterminacy problem. It stems from the fact that organic systems are selected for complex causal roles.

To determine the function of a trait, according to an etiological theory of functions, one asks, “what did past instances of that type of trait do that caused that trait to be selected?”.

Different descriptions of the function of a trait can be had by focusing on different aspects of the complex causal role for which it was selected. As a rule, all biological traits that have functions will have the ultimate telos of enhancing (inclusive) fitness, but there are also the more specific things they did that caused their selection.

Finally, some proponents of teleological theories do not think that content is determinate in the cases used to illustrate the alleged problem, or that it is determinate in the ways that have been mentioned. Dennett, whose theory of content has evolved into a teleological theory, maintains that indeterminacy of content is unproblematic (Dennett 1995). Papineau (1997) also maintains that content is indeterminate, in the case of a simple system, like that of the frog, on the assumption that such creatures lack a belief-desire psychological structure. Sophisticated Concepts and Capacities

The weightiest objection to teleological theories of content, and the hardest to assess, is that it is unclear how such theories could explain our most sophisticated concepts and capacities. No naturalistic theory of content, at this time, makes plain how we can, for example, think about democracy, virtue ethics, quarks, or perhaps even tomorrow. However, it is argued that teleological theories of content have a special problem in this respect (e.g., Peacocke 1992). The thought is that they may have some hope of working for contents that concern things that impact on fitness — food, shelter, mates, etc. — but that they are, in principle, unable to deal with contents that cannot have impacted on fitness, or not in any suitably selective way.

This objection is hard to assess for a number of reasons. One is that there are many different kinds of sophisticated concepts and capacities, and accounting for them all is a very large task. Another is that, while the objection is sometimes posed as an objection to all teleological theories, different versions of teleosemantics will address it in very different ways. Yet another is that teleological theories are least well developed with respect to such hard cases, and yet we might allow that it is still early days with respect to their development.

Recall that, for Papineau, the content of a desire is primary, and the content of the desire is given by the conditions which it is the function of the desire to bring about. We might suppose that the desire to detect a quark might tend to cause quark detection. We might also suppose that being a successful scientist might contribute to one’s fitness, and detecting a quark might contribute to being a successful scientist. Thus, it might be argued, it is the function of the desire to detect a quark to bring about quark detection, and thus the content of the desire is that a quark be detected. So far, so good. But a worry is that this mode of analysis will be too imprecise for the work at hand. Consider also the following scenario. The desire to detect phlogiston might tend to cause oxygen detection (i.e., oxygen which is mistaken for phlogiston). Further, being a successful scientist might contribute to one’s fitness, and seeming to have detected phlogiston by really having detected oxygen might contribute to being a successful scientist. Thus it would seem that, in this scenario, and according to Papineau’s theory, PHLOGISTON means oxygen.  [I don’t see a problem with that-fly or small dark flying object for the frog]


Neander, Karen, “Teleological Theories of Mental Content”, The Stanford Encyclopedia of Philosophy (Summer 2004 Edition), Edward N. Zalta (ed.), URL =


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