Given the way the computer has, since its early years, served as a model for the mind, we should not be surprised that quite specific analogies suggest themselves to philosophers, psychologists and latterly sociologists and archaeologists. I want to focus on just one of these, the idea that the mind might have innate units which do a very specialised job for us. The idea is that the mind is modular, an idea which has received prominence through the widely publicised work of the archaeologist, Steven Mithen. Mithen identifies three modules for social intelligence, natural history and technical intelligence respectively. Cosmides and Tooby, associated with the theory of the mind as like a Swiss army knife, mention about a score1 including a theory of mind module, a logico-mathematical module, a social-exchange module and more. These modules are separate and it is either hard or impossible for information to flow from one to the other. It seems that advocates of modularity think, constantly, in terms of a physical analogue. (A give away is Mithen’s observation that Cosmides and Tooby treat the mind as one treats and other organ of the body [my italics] – it is an evolved mechanism). The mind has modules or parts just as a machine has parts. The mind is the ‘machine in the machine’. So in the background is a largely unstated form of the identity theory of mind and brain.
One reason for believing in modularity2 is that there are certain capacities which human beings have which are so complicated that they defy the usual explanation that they could be acquired through learning. Language is the paradigm. Language is so complex that it is reckoned impossible that human beings should acquire such competence in it by the age of five without the aid of dedicated hard wiring. There is at least an innate syntactic module dedicated to language acquisition.
Now I must say that I am not convinced by Chomskyite arguments that we could not have learnt human language without some innate grammatical structures. But let’s suppose that it is true. The problem is that the modularists apply this reasoning to eases where there is just no reason to suppose that acquiring information is that difficult. Let’s look at the cases in which Mithen is interested, – technology, social relations and natural history. None of these are areas in which the child’s acquisition of information is so comprehensive and rapid as to be hard to explain on the assumption that she learns from experience. The language model is simply inappropriate here. Children are born into a linguistic community. Innovation is not what is at issue here. What is being confused here is the problem of understanding the rapid acquisition of a complex skill and the problem of understanding why our precursors were stuck in a technological warp.
Mithen’s problems are very specific and distinct from those of the modularists in the other social sciences. What puzzles him, inter alia, is why early humans were not innovative. Why did early humans not invent axe-handles or multi-component tools and why was their diet largely limited to big game? Mithen’s answer to his questions marks the difference between his views and those other modularists on which he draws. He thinks that early humans had, for instance, the technology module but not having that language-based free-flowing cognitive thinking which crosses the modules they were limited in their inventiveness in improving their tools. What they needed was the sort of considerations of parallels, metaphors and analogies which modern cognitive thinking brings. In modern man the modules are no longer isolated. Well, there are all sorts of explanations one might offer as to why societies are conservative or non-innovative and anthropologists will offer various answers. Of more philosophical consequence is Mithen’s explanation of the varied diet of later humans. The ability to predict animal behaviour came when human hunters began to place themselves within the mind of the hunted, using the social skills of simulation which belong to the social module. So the extension of the social module to natural history was an example of free flowing cognitive process Hence more successful and varied hunting derives from an anthropomorphism which also shows itself in totemism. Here he draws on recent suggestions by philosophers and psychologists that our knowledge of other people is based on simulation. But why should we believe this? I do not have to place myself in the mind of the rabbit in order to work out that it will dodge from side to side and regularly double back when I pursue it. I learn this from observation.3
There could be many reasons why early humans only hunted big game. They discovered methods of hunting which suited them well and they saw no need to change. Perhaps they did not like the taste of small game and fish. Indeed why should we ascribe a more varied diet to infiltration of the natural history module by the social, assisted by the free-flowing cognitive powers of general intelligence? We can explain it just as well in terms of cultural inertia. Czechs and Finns do not ascribe the fact that the only fungi the British eat are mushrooms to defective cognition, and although the French probably put down the fact that we don’t eat snails or frogs to our cognitive short-comings, I am inclined to think this an error on the part of the French. No more am I inclined to conclude from the startling fact that only the British and the Australians know how to make a decent cup of tea that other nations are cognitively inferior. Equally the fact that early humans did not use bone and ivory might, for all I know, be related to cultural matters. Perhaps they believed it was wrong or perhaps it was simply something they did not do. After all, the fact that I don’t wear a bone from my grandmother’s body through my nose is not to be ascribed to the fact that my technology module is not assisted by free flowing cognition.
There are two strong arguments against modularity, the first familiar to philosophers as the holism of the mental. The isolation thesis faces a very general difficulty. Are we to assume that these modules are so disconnected from each other that elements of one are not used in another? But this is impossible. A parent, feeding its child (social intelligence), needs to know that this is edible fruit and not a piece of wood (natural history) and the technologist, making a hand axe, needs to know that this is a piece of flint which gives a sharp edge and not chalk, which does not (natural history). Indeed the holism thesis maintains that to count at all as believing a certain proposition it is necessary that I believe lots of other propositions. If a man intends to make an axe and believes he is doing so, then he has beliefs, true or false, about the properties of the material he is using and about the uses to which it will be put etc.
Secondly, let us suppose with Gardner4 we all possess a module for logico-mathematical ability which in some of us is more advanced or developed than in others. Some of us more readily perform calculations and pick up new ideas in maths. Now such an ability rests on more primitive accomplishments such as the ability to count or, more primitive still, the ability to discriminate between different things or to identify and re-identify things. Nobody above a vegetative state lacks these capacities. Likewise technological and social modules require more primitive capacities. In the latter, beyond the relatively sophisticated capacity to tell that somebody is uncomfortable or being untruthful, lies the more primitive capacity to recognise a smile. But beyond even this lies the capacity to identify and reidentify people. The supposed modules rest in a more or less undifferentiated mass of capacities that we humans share with the more responsive animals like dogs, cats and primates. If you must have a spatial metaphor think of them as branches growing from a single trunk but varying in size and degree of development. Isolated they cannot be for they share a primitive basis.
Finally, let’s return to the analogy with computers. Suppose I decide to add a spelling check module to my computer. In place, it checks words against a list. Analogously we might imagine that, when looking for a tool, a technology module checks the possibilities of a stick against a template. But note that the computer module acts immediately. The computer does not have to learn how to check and, were our technological competence parallel, we should not have to learn how to handle a chisel or get better as we practice with it. But competence, for humans, is a matter of practice. Cosmides and Tooby may argue that their sorts of modules are different; they need a good deal of practice to get off the ground. But now the analogy between soft-ware and mental modules is so stretched that it no longer seems very natural to use the word ‘module’ at all. Why not apply Occam’s Razor, beloved of the scientistically inclined, and simply excise all reference to innate modules? These are skills we learn.
I think it is a mistake to distinguish between the mind and its contents as modularists commonly do. If; for example, what is not the case, beliefs were all that fell under the heading of the mental, then the totality of beliefs would be equivalent to the mind. Try not to think of the mind as a theatre or a cathedral ( and the cathedral is the dominating analogy of Steven Mithen) which is something which could be empty. Think of it rather like a crowd of people. If there are no people there is no crowd. What belongs to the mind is a property of the person in question, for the mental consists in thinking, acting, imagining, believing etc. and these are adverbial forms which need a person to possess them. These belong with the things we humans do and, once we see this, we understand that dividing them up is a matter of intellectual convenience and not a matter of finding “the joints in nature”.
Modularists are in a muddle over the isolation thesis. What does it mean to say they are isolated? Does it mean that no information flows from one to the other or that it is just very hard. Either seems at variance with the facts. I believe that talk of modules and their fertilising by free flowing cognition is merely an inferior and accident-prone way of saying what we already know without their help, that it took a long time for mankind to move from using hand axes to making axes with halts. There is no very clear way in which we confirm the modular hypothesis as against rival explanations. Might modules eventually be seen in the way sub-atomic particles have been “seen” through the cloud chamber track or the electron microscope? Might we eventually watch the modules at work in a living brain, something like watching a programme at work in a computer? Either surely founders on the problem of multiple realisation. If I can map the brain events which occur when you are thinking of the Albert Hall, there is no reason to suppose they are structurally identical (isomorphic) with those which occur when I think of the Albert Hall. Indeed there is evidence against it. Of any brain events in any particular individual we could not know that those represent a module because modularity might be differently realised in another person’s brain. And since modularity is presented as a discovery about our mind of which we were previously ignorant, we could not even identify a module by the circuitous route in which we could find that certain brain events and certain memories are parallel or interdependent; by seeing that they occur at the same time. I suspect that, like much of what passes for “cognitive science”, the modular theory of the mind is really pseudo-science. And as for innovation, there may not be much more to be said than “Somebody thought of it”.
1 Leda Cosmides and John Tooby. “Cognitive Adaptations for Social Exchange” in J.H. Barkow, Leda Cosmides and John Tooby eds. The Adapted Mind. Oxford 1992
2 Steven Mithen. The Prehistory of the Mind. Thames and Hudson 1996 pp.43-4
3 R.A.Sharpe. “One cheer for simulation theory.” Inquiry. 40 1997 pp. 115-32
4 H.Gardner. Frames of Mind: the theory of multiple intelligences. Basic Books New York 1983