Introduction

When I woke up a few days ago, the following thoughts ran through my mind. ‘I need a haircut. If I don't get it first thing this morning, I won't have another chance for two weeks. But if I go to the barber down the road, he'll want to talk to me about philosophy. So I'd better go to the one in Camden Town. The tube will be very crowded, though. Still, it's a nice day. Why don't I just walk there? It will only take twenty minutes. So I'd better put on these shoes now, have breakfast straight away, and then set out for Camden.’

This is a paradigm case of what I shall call ‘means-end reasoning’. In such reasoning, we consider the consequences of various courses of action, and choose the course best suited to our overall purposes. I take it to be uncontroversial that all human beings are capable of such means-end reasoning, and that this kind of reasoning guides many of our actions. Indeed I take it that this power of means-end reasoning is one of the most important differences—if not the most important difference—between humans and other animals.

Yet for some reason this topic has become unfashionable. Meansend reasoning seems to have disappeared from the theoretical agenda of many of those you would expect to be most interested, namely those who work on human cognition in a comparative or evolutionary context. There are now large industries devoted to theory of mind, to language, and to other ‘modules’ putatively characteristic of human cognition.