Between the publication of The Analysis of Matter in 1927 and the year 1935, when he began the work that issued in An Inquiry into Meaning and Truth, Russell did very little 'serious philosophy.' He was schoohnastering and pamphleteering. He was also busy lecturing to western civilization on the meaning of the good life and publishing a string of what he later called "pot boilers." They were in fact sturdy volumes, still read and readable, collections of wisdom and banality - tempered with wit. We can pass smoothly over this (reserving it for the next chapter) in order to put Russell's later philosophy into some kind of perspective. By 'later philosophy' I refer primarily to his two major books Inquiry into Meaning and Truth (1940), and Human Knowledge: Its Scope and Limits (1948), as well as his "Reply to My Critics" in The Philosophy of Bertrand Russell (1944), and his more recent My Philosophical Development (1959). These books constitute only a fraction of his production during this time, but they include all that is germane to our topics. Even so, there are innumerable ideas, and several entire themes in these books that I shall exploit but scarcely mention, for reasons of order and space.