 In the spring of 1948, Maritain returned to Princeton as Professor of Philosophy; he also lectured at a number of American universities (particularly at the University of Notre Dame and the University of Chicago), but frequently returned to France to give short courses in philosophy—notably at ‘L’Eau vive’, in the town of Soisy, near Paris. During this time, in addition to his work in political philosophy (cf. above, as well as Le philosophe dans la cité, 1960), Maritain published on aesthetics (Creative Intuition in Art and Poetry, 1953), religion (Approches de Dieu, 1953), moral philosophy (Neuf leçons sur les notions premières de la philosophie morale, 1951; La philosophie morale, 1960), and the philosophy of history (On the Philosophy of History, 1957).