   Russell’s work from the period after the publication of Principia Mathematica of 1910 shows applications of this general philosophical approach to non-mathematical domains. In particular, his work over the next two decades shows concern with the attempt to provide analyses of the notions of knowledge, space, time, experience, matter and causation. When Russell applied his analytic methodology to sciences such as physics, again the goal was to arrive at a “minimum vocabulary” required for the science in question, as well as a set of basic premises and general truths from which the rest of the science can be derived. We cannot delve into all the details of Russell’s evolving analyses here. However, according to the views developed by Russell in the mid-1910s, many of the fundamental notions in physics were thought to be analyzable in terms of particular sensations: i.e., bits of color, auditory notes, or other simple parts of sensation, and their qualities and relations. Russell called such sensations, when actually experienced, “sense”. In particular, Russell believed that the notion of a “physical thing” could be replaced, or analyzed in terms of, the notion of a series of classes of sensible particulars each bearing to one another certain relations of continuity, resemblance, and perhaps certain other relations relevant to the formulation of the laws of physics (OKEW, 86ff; RSDP, 114–15; UCM, 105). Other physical notions such as that of a point of space, or an instance of time, could be conceived in terms of classes of sensible particulars and their spatial and temporal relations (see TK, 77; OKEW, 91–99). Later, after abandoning the view that perception is fundamentally relational, and accepting a form of William James’s neutral monism, Russell similarly came to believe that the notion of a conscious mind could be analyzed in terms of various percepts, experiences and sensations related to each other by psychological laws (AMi chaps. 1, 5; OOP chap.  26; cf. PLA, 277ff). Hence, Russell came to the view that words as “point”, “matter”,“instant”, “mind”, and the like could be discarded from the minimum vocabulary needed for physics or psychology. Instead, such words could be systematically translated into a language only containing words representing certain qualities and relations between sensible particulars.