ABSTRACT
It is easy to choose a subject for a distinguished lecture like this, before a large and critical audience with a wide range of interests. You need a topic that is absolutely contemporary, but somehow perennial. It should survey a broad field, without being superficial or vague. It should probably bear some relation to economic policy, but of course it must have some serious analytical foundations. It is nice if the topic has an important literature in the past of our subject-a literature which you can summarize brilliantly in about eleven minutes-but it better be something in which economists are interested today, and it should appropriately be a subject you have worked on yourself. The lecture should have some technical interest, because you can’t waffle for a whole hour to a room full of professionals, but it is hardly the occasion to use a blackboard.
