8.6.2—
Instantiation, Realization, Vindication

Now even if it is possible to coordinate MR-semantic properties with causal role, this is not enough for the vindication of intentional psychology. For that one also needs it to be the case that coordinating the MR-semantic properties of representations with their causal roles secures the further coordination of the mental-semantic properties of mental states with their causal roles. Presented in the way the case was originally presented, when we assumed that the "semantic" properties of mental states were the very same properties as those of their representations, securing this further coordination seemed almost trivial. The argument for it is expressed by this argument presented earlier in the chapter:

Argument V2

(1) Mental states are relations to mental representations.

(2) Mental representations have syntactic and semantic properties.

(3) The syntactic properties of mental representations determine their causal powers.

(4) All semantic distinctions between representations are preserved syntactically.

(5́) There is a strict correspondence between a representation's semantic properties and its causal powers.

(6́) A mental state M has semantic property P if and only if it involves a representation MR that has semantic property P .

\ (7́) There is a strict correspondence between a mental state's semantic properties and its causal powers.

But of course once one has distinguished different kinds of semantic properties, the argument has to be adapted as follows:

Argument V3

(1) Mental states are relations to mental representations.

(2) Mental representations have syntactic and MR-semantic properties.

(3) The syntactic properties of mental representations determine their causal powers.

(4) All MR-semantic distinctions between representations are preserved syntactically.

(5^* ) There is a strict correspondence between a representation's MR-semantic properties and its causal powers.

(6^* ) A mental state M has mental-semantic property P if and only if it involves a representation MR that has MR-semantic property X .

\ (7^* ) There is a strict correspondence between a mental state's mental-semantic properties and its causal powers.

The issue here turns upon (6^* ), the claim that mental-semantic properties of mental states can be coordinated with MR-semantic properties of representations, and the inference to (7^* ), the claim that mental-semantic properties of mental states would thereby be coordinated with causal powers. In order for (6^* ) to be true, the mental-semantic properties of mental states would have to be at least correlated with the MR-semantic properties of representations. But in order for this argument to provide a vindication of intentional psychology, something more is required: one must be able to show that the MR-semantic properties of representations determine the mental-semantic properties of mental states. For in order to vindicate something, one must show that it could be the case. To vindicate intentional psychology, one would have to show that the mental-semantic properties of mental states can be coordinated with causal roles, and not merely show what benefits would be derived if they were so coordinated. Given that we can show that MR-semantic properties of representations can be coordinated with causal roles, we would still have to show that, as a consequence, mental-semantic properties of mental states would be coordinated with causal role as well.

Now what sort of account of mental-semantic properties would be

needed to achieve this end? What is required is an instantiation analysis of mental-semantics in terms of MR-semantics—a realization account is not enough. For recall a key difference between instantiation and realization: since an instantiation account provides conditions from which one can infer the instantiated property, it provides a vindication of existence claims for that property, given that the instantiating properties are satisfied. But with a realization account, no such benefit accrues: since the realizing properties are not a sufficient condition for the realized property, they do not provide proof for someone who doubts that such a property can be realized. Now we are seeking an account that vindicates the claim that the mental-semantic properties of mental states can be coordinated with their causal powers. An account of how mental-semantic properties are instantiated through the MR-semantic properties of representations could provide such a proof, because one would be able to infer the mental-semantic properties of the mental states from the MR-semantic properties of the representations. A realization account, on the other hand, merely presupposes that there is some special relationship between the properties picked out in the intentional idiom and those picked out by the functional-causal account, without either specifying the nature of the relationship or showing why it obtains. Such a presupposition may have great advantages if you are doing empirical psychology, because you can do your research without waiting for definitive results of debates about dualism, reduction, supervenience, or psychophysical causation. But for this version of the vindication of intentional psychology to work, we must not assume such a special connection, because the possibility of such a connection is precisely what has been called into doubt . If someone doubts that the semantic and intentional properties of mental states can be coordinated with naturalistic properties, and one gives a realization account for the intentional and semantic properties of mental states that just assumes that they are specially connected to some naturalistic properties, one has not assuaged the doubt so much as begged the question.