In this essay, I explore the role of philosophy in politics and public policy along one dimension that is suggested by the question ‘Does reason have a place in the shaping of public policy and institutions?’ In considering this question, I focus on the factors that prevent reasoned argument from influencing political process and outcome. Among the factors standing in the way of reason, two, I think, are of special importance. The first is the dominance of interests, and the second is the dominance of fixed ideas rooted not in interests but in myth and fantasy. I begin with the role of interests in politics arguing that interest provides a limited role for reason, but that this role erodes the more interest is an expression of greed. I then turn to belief and the way belief systems operate as the more powerful of the two factors excluding reason from politics.

While interest-based politics can create space for reason, what now tends to dominate in politics is not interests so much as other factors operating on an altogether different plane. These are the factors associated with fixed ideas, convictions made impervious to any doubt by forces over which reason has no power. It is possible, of course, to attempt to treat conviction as a kind of interest. We can, after all, be said to take an interest in our belief systems. Yet, an important distinction can still be drawn, within the set of objects in which we might take an interest, between those associated with belief and those associated with the narrower matter of economic well being.