Gerard O'Brien

Stich begins his paper "What is a Theory of Mental Representation?" by noting that while there is a dizzying range of theories of mental representation in today's philosophical market place, there is very little self-conscious reflection about what a theory of mental representation is supposed to do. This is quite remarkable, he thinks, because if we bother to engage in such reflection, some very surprising conclusions begin to emerge. The most surprising conclusion of all, according to Stich, is that most of the philosophers in this field are undertaking work that is quite futile: " It is my contention that most of the players in this very crowded field have _no_ coherent project that could possibly be pursued successfully with the methods they are using. " Stich readily admits that this is a startling conclusion; so startling, he thinks, that some may even take it as an indication that he has simply "failed to figure out what those who are searching for a theory of mental representation are up to". But it is a conclusion that he is willing to stand by, and he sets about it defending it in the body of his paper

Any creature that must move around in its environment to find nutrients and mates, in order to survive and reproduce, faces the problem of sensorimotor control. A solution to this problem requires an on-board control mechanism that can shape the creature’s behaviour so as to render it “appropriate” to the conditions that obtain. There are at least three ways in which such a control mechanism can work, and Nature has exploited them all. The first and most basic way is for a creature to bump into the things in its environment, and then, depending on what has been encountered, seek to modify its behaviour accordingly. Such an approach is risky, however, since some things in the environment are distinctly unfriendly. A second and better way, therefore, is for a creature to exploit ambient forms of energy that carry information about the distal structure of the environment. This is an improvement on the first method since it enables the creature to respond to the surroundings without actually bumping into anything. Nonetheless, this second method also has its limitations, one of which is that the information conveyed by such ambient energy is often impoverished, ambiguous and intermittent

Dienes & Perner offer us a theory of explicit and implicit knowledge that promises to systematise a large and diverse body of research in cognitive psychology. Their advertised strategy is to unpack this distinction in terms of explicit and implicit representation. But when one digs deeper one finds the “Higher-Order Thought” theory of consciousness doing much of the work. This reduces both the plausibility and usefulness of their account. We think their strategy is broadly correct, but that consensus on the explicit/implicit knowledge distinction is still a fair way off.