This is Volume XVII of twenty-two in a series on 20th Century Philosophy. Originally published in 1959 it is a contribution to the History of Modern Philosophy under the heads: first of different Schools of Thought-Sensationalist Realist Idealist Intuitivist; secondly of different Subjects-Psychology Ethics Aesthetics Political Philosophy Theology. This is a collection of papers by George Edward Moore Emeritus Professor of Philosophy and Fellow of Trinity College in the University of Cambridge.