Sensation, memory and imagination in Bertrand Russell's philosophy 1910-1926

The aim of this dissertation is to examine the development of Russell's theory of cognition in the period from 1910 to 1926. Russell's theory of cognition consists of a set of principles that explain how our cognitive faculties of sensation, perception, memory, imagination, introspection, etc., contribute to our knowledge of the external world. At the core of the theory of knowledge lie the four experiential cognitive faculties of sensation, perception, memory and imagination. I am interested in these cognitive faculties since I believe that the theory of cognition, which has been overlooked in the scholarship, is an integral part of Russell's epistemology and deserves to be a part of the analysis of Russell's epistemology of the stipulated period. The period from 1910-1926 includes what is known as the acquaintance period (1910-1918), and the neutral monist period (1919-1926). I argue that in the acquaintance period Russell believes that the foundation of the theory of knowledge is the theory of experiential knowledge. For him experiential knowledge is grounded in acquaintance and this notion implies a theory of the cognitive faculties - sensation, perception, memory and imagination, and their sub-types. Through knowledge by acquaintance Russell hopes to explain the conditions of the most certain knowledge there is, and distinguish it from knowledge by description which is derivative, conceptual, complex, and dubitable. The theory of cognition under the acquaintance theory of knowledge faces challenges, such as distinguishing between certain cognitive faculties, or explaining how memory, and especially immediate memory, works, difficulty in accounting for our knowledge of the existence of the subject of cognition, etc. Another issue which Russell faces with in the theory of cognition from the acquaintance period is that it could turn out that the most certain knowledge is confined to knowledge of the specious present only. This possible outcome made scholars question the cognitive status of knowledge by acquaintance. In 1918 Russell expresses doubts that the theory of knowledge by acquaintance explains our knowledge of the external world. In 1919 he gives up his theory of knowledge by acquaintance and embraces a new one based on the principles of neutral monism. An initial attraction of the theory of neutral monism is that it made the picture of knowledge simpler by abolishing, or perhaps, by explaining it in new terms, a crucial distinction in the model of knowledge by acquaintance - the distinction between act of cognition (which is mental), and object of cognition (which is physical), and thus, dispensed with certain entities, such as the subject of cognition, which Russell was hesitant about from the very beginning. The central claim of the theory of cognition according to neutral monism is that all knowledge, experiential knowledge included, is derivative or mediated, and therefore, subject to error and skeptical doubt. Thus, even the most certain knowledge (perceptual knowledge) is subject to error. This puts an end to the distinction between direct and derivative knowledge which Russell viewed as important in the acquaintance period, and in a sense, makes the account of knowledge simpler. This, however, comes at the price of exposing all knowledge to skeptical doubt a lot more than it was possible in the acquaintance theory. Whatever the challenges of the new theories of sensation, perception, memory, and imagination, the textual evidence clearly shows that, despite all the changes surrounding the theory of knowledge in both periods, Russell's interest in the theory of cognition was growing and the theory of cognition was becoming increasingly complicated, of which The Analysis of Mind (and the later neutral monist texts) is evidence. I believe that there is a lack in the scholarship of a comprehensive analysis of the development of Russell's ideas about the main experiential cognitive faculties in both periods