The limits of rational choice or why do economists become parents ?

I feel in an awkward position presenting this paper to an inter-disciplinary audience. While economists have ignored caring as irrational behaviour, other disciplines have frequently considered the extent to which rationality and caring are disparate or compatible modes of thought, and until recently, have not tried to force caring into the specific mould of rational choice theory. In recent years, however, an unfortunate imperialism by economic man has resulted in a variety of not obviously economic issues being analysed through the lens of rational choice. While the inter-disciplinary character of such work is very welcome, the actual form it has taken is not. Economic man seems extraordinarily reluctant to learn from his colleagues in other disciplines, especially when their accumulated wisdom suggests that rational choice models are not the best way to analyse such " non-economic " phenomena. At the same time some economists are discovering that rational choice models are not always the best way to investigate some more traditionally economic phenomena, such as the behaviour of stock markets and the adoption of new technologies. In exploring these topics, it has been suggested that norms and fashions may play an important role in individual behaviour. Interactions between individuals then lead to a far greater complexity in the macro behaviour of the system than the traditional economic analysis of market equilibria would suggest. In this paper, I shall look at some of the ways in which models of individual behaviour might be constructed to take account of caring behaviour. I shall argue that those models that use just small modifications of rational choice theory do not go far enough away from the parent theory to be useful. However I remain committed to the building of some sort of model of individual caring behaviour. This is because if caring behaviour is to be taken seriously in economic and social