It is possible to give a definition of realism about folk psychology that might be acceptable to those mentioned above. Kim’s and Fodor’s realism can be taken to commit us to the existence of a specific property. If we take folk-psychological predicates to express specific properties, then we are realists about folk psychology in the spirit of the common-sense view of the discourse. But this seems to be too restrictive; realism does not require this much. It requires only that there be some properties of the agent that can make folk-psychological propositions true. In Dennett’s case one can say that there are properties of a triangle, allowing for the calculation of its centre of gravity, which can make the calculation true. Similarly, attitude ascriptions can be calculated and can be true: mental states are calculated by reference to patterns of the agent’s behaviour.
These abstract properties are not part of the world in the same way that observable physical properties are, but this is not even necessary for a realist interpretation of the discourse about them. As John Heil (1999: 200) points out correctly:
Realism about a given predicate, ‘Φ’, requires only that ‘Φ’ applies truly to objects in virtue of properties actually possessed by those objects. Realism does not require that ‘Φ’ designate a property shared by every object to which it truly applies.Footnote 2
The case is similar with epiphenomenalism: either we allow causally inert properties, or, if we insist on the causal analysis of ‘property’, we say that mental state ascriptions describe causally inert epiphenomena of causally efficacious processes. Thus, the common ground can be put this way: mental state ascriptions can be true in virtue of the agent’s real properties—without further restrictions on the number or nature of the properties in question.
This said, we have not yet agreed on the meaning of realism about folk psychology. The central claim of realism about any kind of discourse is frequently put forward as a conjunction of two theses (cf. Wright 2002: 207):
semantic thesis: the statements in the discourse have a content representing aspects of the real world;
metaphysical thesis: the real world is furnished with facts that these statements can represent.
This is the core of the positions discussed above: folk psychology is a descriptive discourse representing some existing aspects of the world.
It seems possible, however, to give a realist interpretation of a class of statements without accepting that there are facts to be suitably represented in the discourse—i.e. it is possible to deny the metaphysical thesis while maintaining a realist interpretation of the discourse. This is to say that given the nature of the discourse it conforms to the semantic claim (i.e. it aims at a true representation of some aspects of the world), but the real world does not contain facts that the statements could represent. Realism construed in this way is an attitude concerning the proper interpretation of the discourse—a view about its nature, and not about the metaphysics of the facts (allegedly) represented in it. It is thus the semantic thesis only that is essential for a realist interpretation of any kind of discourse, and not its conjunction of the metaphysical theses.
For instance, if we consider that statements in the discourse about witches aspire to describe some aspects of the world, we may well believe that it fails in this aspiration—thus we interpret the discourse in a realist way, but take an anti-realist stance towards its metaphysics. Realist interpretation does not require us to believe that the discourse is true, and that the world is furnished with facts that the discourse is fitted to represent: it is enough to believe that the role of the discourse is to represent these putative facts. In the case of folk psychology, eliminativists (Churchland 1981) hold a position like this. They think that folk psychology is, by its nature, a fact-stating discourse, an explanatory theory; but there are no facts in the world that could make its statements true, so folk psychology is false. Eliminativists reconstruct folk psychology as if it was an empirical theory, a case par excellence of fact-stating discourses, and argue that it fails to live up to the standards.
As Bas van Fraassen (1980: 11) aptly puts it: a fundamentalist theist, an atheist, and an agnostic can agree on how to interpret sentences about God or the angels, but they cannot agree with liberal theologians who hold that these sentences should not be interpreted literally. If this casting is carried over to the present context, then Fodor plays the role of a fundamentalist theist, and eliminativists play that of the atheist: they believe folk psychology to be fact-stating in a literal sense. The liberal theologian is Dennett, who rejects the literal reading, but maintains that the discourse is fact-stating in an abstract-calculative sense.
For van Fraassen interpreting a discourse as fact-stating does not amount to realism, as for him it also entails a commitment to truth. I would rather say that in the previous passages we met the realist interpretation of folk psychology in three versions. The criterion of acceptance of a statement follows from the interpretation of the discourse to which it belongs—in the case of descriptive discourses this criterion is truth. Therefore the interpretation of a discourse is logically prior to the criterion of acceptance for statements in the discourse, and following our interpretation we can also undertake or withdraw from ontological commitments to the entities postulated in it. The criterion of acceptance depends on how we look at the discourse in which the statement is made. We accept statements like ‘Sherlock Holmes enjoyed opium’ under very different circumstances if Conan Doyle’s stories are interpreted as historical chronicles and not as short stories, and our ontological commitments to the entities postulated in them may be adjusted accordingly.
These three versions of realist interpretation agree that the essential property of folk psychological ascriptions is their truth conditions picking out states of affairs in the world. They differ with respect to the prospects of fulfilling these conditions and the nature of the facts that could fulfil them. This is why we can talk about three versions of realist interpretation. The first of these, Fodor’s, is the strongest one. It maintains that folk psychology serves to describe the mental constituents of the world as they are, and it succeeds. The second version, Dennett’s, also maintains that folk psychology aims to describe some facts that are accessible from a specific calculative stance, and that it succeeds; but its truth-makers do not reside on the level of the properties ascribed, but on a sub-personal level. The third version, the eliminativist one, holds that although folk psychology is a descriptive theory, its function is to state facts, and in this it fails systematically. They are all realists about folk psychology because they share the view that the discourse is used for stating facts about the real world, only they judge its success, or the way it succeeds, differently.
One final question must now be answered in order to understand realism about folk psychology: what does it mean to say that folk psychology is a fact-stating discourse? This is to say that folk psychology serves the purposes of true description of some aspects of the world, and if it succeeds then its truth is grounded in how things are in the world. This is shared by all three versions: there are functions specifying how folk-psychological propositions should map semantically onto the world. These propositions have correspondence truth conditions as their truth is grounded in how things stand. Thus, following Devitt (1991: 29), we can list the conditions on which the truth of these propositions depends. If interpreted in a realist way a folk-psychological proposition is true if and only if:
the sentence expressing the proposition is well-formed,
the entities postulated in it exist,
there are proper semantic relations between the discourse and the world.
The realist interpretations can be grouped from this angle too. The first condition is typically not challenged: the syntax of folk-psychological propositions does not pose a problem. Fodor’s realism holds that folk-psychological propositions can describe some region of the world and their structure is a good guide to knowing how things stand in that region. For Dennett, the structure of propositions is not a good guide, thus he envisions the relevant semantic relations differently, but believes that these relations hold. Eliminativists argue that the semantics of folk psychology is that of a fact-stating discourse, its propositions should semantically map onto entities that make its law-like generalisations true, but deny that these entities are there in the world.
To sum up this section: realism about a given discourse is a position about its nature—its function or role in our form of life, logic, Wittgensteinian grammar. A discourse can be interpreted in various ways. Realist interpretations answer the question about the relation of world and discourse by saying that it is of a fact-stating character, i.e. its role is to give a true description, which is acceptable by discourse-independent facts, of a region of the world. If we share this conviction, we give a realist interpretation of folk psychology. This is not too restrictive, as the fact-stating character can be reconstructed in various ways. If we give up this conviction, then we deny that the discourse is descriptive of some region of the world. Thus we do not expect the discourse to be fitted to represent facts.