Online research in philosophy

This book focuses on Russell's work from 1905 to 1919, during which period Russell attempted a reductionist analysis of empirical knowledge.

Sense data are the alleged mind-dependent objects that we are directly aware of in perception, and that have exactly the properties they appear to have. For instance, sense data theorists say that, upon viewing a tomato in normal conditions, one forms an image of the tomato in one's mind. This image is red and round. The mental image is an example of a “sense datum.” Many philosophers have rejected the notion of sense data, either because they believe that perception gives us direct awareness of physical phenomena, rather than mere mental images, or because they believe that the mental phenomena involved in perception do not have the properties that appear to us (for instance, I might have a visual experience representing a red, round tomato, but my experience is not itself red or round). Defenders of sense data have argued, among other things, that sense data are required to explain such phenomena as perspectival variation, illusion, and hallucination. Critics of sense data have objected to the theory's commitment to mind-body dualism, the problems it raises for our knowledge of the external world, its difficulty in locating sense data in physical space, and its apparent commitment to the existence of objects with indeterminate properties.

A full appreciation for Ernst Mach's doctrine of the economy of thought must take account of his direct realism about particulars (elements) and his anti-realism about space-time laws as economical constructions. After a review of thought economy, its critics and some contemporary forms, the paper turns to the philosophical roots of Mach's doctrine. Mach claimed that the simplest, most parsimonious theories economized memory and effort by using abstract concepts and laws instead of attending to the details of each individual event or experiment. For Mach, the individual case never truly repeated in all of its uniqueness, nor was all of the individual detail of a physical element adequately captured in abstract laws and schemata, however necessary these were for the pursuit of science. As can be shown from specific passages, some already published, some not, Mach's elements included physical qualia in nature similar to Russell's unsensed sensibilia, which existed even where there were no conscious observers. An argument will be presented to make the case that Mach believed in the mind-independent elements from the 1870s on, while other aspects of his thought evolved over time; I have thus dated the references to reflect this historical progression. I concentrate on Mach's ontology, as it bears on economy of thought, not his epistemology per se, which might well have been restricted to observable elements/sensations. After his own conversion to neutral monism, in the 1920s, Bertrand Russell echoed Mach's call for a 'future science' capable of handling the 'intrinsic character' of qualitative data directly without the excessive abstraction of physics.

Two concepts of utmost importance for the analytic philosophy of the twentieth century, “sense-data” and “knowledge by acquaintance”, were introduced by Bertrand Russell under the influence of two idealist philosophers: F. H. Bradley and Alexius Meinong. This paper traces the exact history of their introduction. We shall see that between 1896 and 1898, Russell had a fully-elaborated theory of “sense-data”, which he abandoned after his analytic turn of the summer of 1898. Furthermore, following a subsequent turn of August 1900—-after he became acquainted with the works of Peano and later of Frege—-Russell gradually developed another theory of sense-data. With the collaboration of G. E. Moore, Russell reintroduced the term “sense-data” in 1911. Concomitantly with this move, Russell introduced the epistemological term “knowledge by acquaintance”, which came to designate the grasping of sense-data and universals.

A consideration of Mach's elements, his philosophy of neutral monism, and philosophy of physics, especially space and time, much of it based on unpublished writings from the Nachlass and other original sources. The historical connection between Mach and logical positivism is shown to be superficial at best, and Mach's elements are shown to be mind independent natural qualities (world-elements) with dynamic force, not limited to human sensations.

Neutral monism is a position in metaphysics defended by Mach, James, and Russell in the early twentieth century. It holds that minds and physical objects are essentially two different orderings of the same underlying neutral elements of nature. This paper sets out some of the central concepts, theses and the historical background of ideas that inform this doctrine of elements. The discussion begins with the classic neutral monism of Mach, James, and Russell in the first part of the paper, then considers recent neo-Russellian versions in the second half. The chances for a revival of neutral monism are probably slight; its key ideas and starting points lie far from those in contemporary philosophy of mind. A better route might be through the philosophy of science and a deeper understanding of causation.