Abstract
With the aim of giving a naturalistic foundation to the notion of mental representation, Fred Dretske (1981;1988) has put forward and developed the idea that the relation between a representation and its intentional content is grounded on an informational relation. In this explanatory model, mental representations are conceived of as states of organisms which a learning process has selected to play a functional role: a necessary condition for fulfilling this role is that the organism or some proper part of it (presumably situated in the brain) is a natural indicator of the occurrence of a determinate type of event in the environment of the organism (or in the organism but outside of the proper part serving as the indicator). A state of the organism is a natural indicator of a type of event if and only if it carries information about the occurrence of that type of event. Jerry Fodor (1987) has devised and followed another strategy which consists in considering the relation between a mental representation and its intentional object as a relation of lawful, or nomic, dependence. A representational state of an organism has an objective content in virtue of the existence of a relation of nomic dependence between this state - presumably a property of the brain of the organism - and some objective property in the world. This dependence also creates a regular correlation between the occurrences of representational states of a certain type and the states of affairs whose type is their representational content. Both approaches encounter indeterminacy problems: for each, there exist situations in which the explanatory model chosen - information flow or nomic dependence - does not succeed in selecting, purely on the basis of the constraints characteristic of that model, one out of several potential contents for a given representational state. In such cases, that state is related to more than one type of events in accordance with the informational or nomic constraints imposed by those theories. In what follows, I examine an attempt by Pierre Jacob (1997) to solve two problems of indeterminacy threatening the informational theory of mental representation. According to Jacob, one of these problems can be solved with the help of the distinction between the source which is the target of the information and the channel over which the information is transmitted, whereas the solution to the other problem requires the introduction of the concept of function. I shall begin with a consideration of the distinction, with respect to a situation of information transmission, between the source and the channel. I argue that both the source and the channel, and thus the information transmitted, depend not only on the external situation which characterises the source, the channel and the receiving organism, but also on the previous knowledge and the informational needs of the receiver. I then try to show that this relativity of information undermines the solution Jacob proposes to one of the problems of indeterminacy of representational content. Finally, I examine the possibility considered by Dretske and Jacob to solve this 'problem of the reference class' due to the mentioned relativity of information, by grounding the flow of information on lawful dependence instead of statistical dependence. I shall propose two arguments showing first that these two groundings are not equivalent and second that nomic dependence is inappropriate as a grounding for information flow. I conclude by suggesting that the problem of the reference class can be solved within the framework of the informational approach, on the condition of enriching it with functional considerations