Abstract

Our politics are increasingly polarised. Polarisation takes many forms. One is increasing clustering or 'ideological consistency,' whereby people hold down-the-line liberal or down-the-line conservative views on a wide range of political issues, even when those issues are orthogonal to each other. Some philosophers think that such clustering is indicative of irrationality, and so if you find yourself in one of several clusters of opinion, you should decrease your confidence that all your political beliefs are true. I argue that the reverse is true, presenting a simple model of belief-formation on which finding yourself in one of several clusters of opinion on orthogonal issues should increase, rather than decrease, your confidence that all your beliefs are true.