Tilly: Bertrand Russell

Russell's (1872-1970) new theory of reality shows the influence of G.E. Moore's theory of sensory materials and physical objects, as well as the influence of Menon's logical realism of object theory. Russell's position underwent many changes during his long philosophical career, but a certain realism was his constant theme, in all his writings, from Philosophical Problems (1911) to Human Knowledge (1948). Like Moore, Russell, in his theory of perception in The Philosophical Question, distinguishes between "sensations" as conscious experiences and the sensory materials we perceive: "Thus, whenever we see color, we have sensations about colors, but colors themselves are sensory materials, not sensations. "However, while Moore interprets sensory materials as public objects that can exist without being perceived, Russell describes them as private objects, for they can only be present to a person and think that they can only exist when they are perceived." "Colors," russell said, "cease to exist when we close our eyes, and if we remove our hands from contact with the table, the feeling of hardness disappears..." Unlike Moore, Russell accepted the idealistic argument in terms of sensory material; their existence is perceived. "Berkeley is right to think that the sensory materials that make up our perception of trees are more or less subjective, because the extent to which these sensory materials depend on the tree depends on us, and to the extent that the tree is not perceived, they will disappear." But his similarities with Berkeley also stop there, because our subjective sensory material mediates our knowledge of the physical object, which has a realist position independent of perceptual behavior. So, what is the basis for accepting physical objects other than sensory materials? Russell admitted that we can never prove the existence of physical objects that lie outside our sensory material, yet he accepted physical realism as the simplest hypothesis to explain ordinary sensory perception. "Every simple principle prompts us to take the natural view that there are indeed objects outside of us and our sensory materials, that they can exist independently of our perception of them."

In Philosophical Questions, Russell extended his theory of realism to universals beyond the physical object, thus combining physical realism with logical realism. By asserting that relational universals such as white and equality are parasocial realities, he develops a theory of universals similar to Plato's theory of forms or ideas. Universals are real entities that do not exist in either the mental world nor in the physical world, but have a potential or logical status. Russell claimed that the mind has a direct knowledge or perception of universality, and that such perception provides the basis for our rational knowledge of transcendental truths. "All prior knowledge is dealing with universals." For example, the arithmetic proposition "2 plus 2 equals 4" is a truth about the reciprocal relationship between the universal "4" and the "2 and 2 whole" as a universal complex. In Russell's view, his logical realism has an intuitive basis and, therefore, has a stronger foundation than the physical realism it has introduced as a mere hypothesis.

The 1914 book Our Knowledge of the External World also appeared under the title Scientific Method in Philosophy, in which Russell transformed the epistemological realism of Philosophical Problems in several important ways. He retains the distinction between the three elements of perceptual knowledge in his early days: (1) "consciousness" or mental perceptual behavior, (2) the "sensory material" or "sensory object" that we perceive, and (3) the perceptual object recognized through contemplation of the sensory material. A "perceptible object" is not something like a table, but a patch of color or sensation that I instantly perceive when I look at or touch a table. Russell no longer believed as much in his earlier works in the hypothesis that independent physical objects are the simplest, and therefore true and correct point of view; he now sees perceptual objects, such as the perceived table, merely as a "logical construction" based on the various representations of the table presented to fixed observers or different observers at the same time or at different times: "All aspects of things are true, and things are only a logical construction." The only statement he makes for his hypothetical theory of construction is: "There is no basis for the truth of this belief, but we have not drawn any positive basis to support it." Russell's theory of the logical construction of physical objects is clearly related to Poincaré's conventionism.

In his 1921 book The Analysis of the Mind, Russell, under the influence of the new American realism, developed his own epistemological position, in which the purely conscious act in his early works was completely abolished, and the "sensory material" or "sensible object"—now commonly referred to as "sensation"—was treated as a real aspect or perspective of the scene, constituting both physical and psychological objects. "Sensations" are neutral entities—that is, they are neither physical nor psychological—as part of a category or set, they constitute physical objects and, when they belong to another set, constitute the mind. "Feelings are shared by both the mental and physical worlds; they may be defined as the intersection of matter and mind," he said. The theory summarized in the above quotation may be described as neutral monism; the ultimate components of reality are all of a kind (monism) and are neither spiritual nor physical (neutralism). The individual mind is a choice of neutral entities; the physical object is another. Knowledge occurs when there is overlap or partial equality between the object of mind and the object of matter. Thus, in perception, the components of certain neutrally viewed scenes of physical objects are also components of our experience; in one context they may be called "psychological" and in another context they may be called "physical". There are "two ways of classifying concrete things, one as 'things' or 'fragments of matter', and the other as sequences of 'perspective scenes', each of which is something that can be called 'experience'". For example, "When I look at the stars, my feelings are: (1) the members of a specific group of things are stars and have something to do with the location of the stars; (2) the members of a special group of things are my experiences, related to my location." The epistemological position associated with Russell's neutral monism is entirely realistic, for the given perspective that is now part of my experience continues to exist as a view of the physical object, even when it is not experienced by me or any other observer.

In the kind of realism offered in Russell's Search for Truth and Meaning, there is little trace of the spectacle realism of perspective in The Analysis of the Mind; rather, it is closer to the apparent realism of his earliest epistemological works. His discussions still focus on our "perspective on the experience of the scene," such as "seeing the sun" or "seeing a cat," on the question of the relationship between the associated physical object. "We have more than one experience of 'seeing the sun'; according to astronomy, there is a large lump of hot matter that is the sun. So, what is the relationship between this mass of matter and the so-called 'seeing the sun' event? There is a causal relationship between the sun and "seeing the sun," and the two are thought to be similar: "The sun looks round in my visual space and is round in physical space. "The existence of the kind of physical object that gives rise to my experience of the vision of the scene, and which may be similar to it, is based on inductive reasoning." Therefore, we have the basis to believe that ... When I 'see a cat', there may be a cat. We can't go any further than 'maybe' because we know that people sometimes see cats that don't exist, such as in dreams. In his recent discussion of perceptual knowledge in The Knowledge of Man (1948), Russell confronted the question here: How and to what extent did perceptual objects become the source of our knowledge of physical objects? He then replied that it was by probabilistic causal inference in accordance with the laws of physics: it was possible to deduce from the perceptual object as a result to the physical object as the cause; but he took a step back and acknowledged that "the relation of the perceptual object to the physical object which is conceived as the kind of perceived is vague, approaching, and somewhat uncertain." "We cannot perceive physical objects in a precise sense." Throughout Russell's long philosophical development, Russell has always been drawn to the question of the relationship between perceptual experience and physical objects, and despite his radical shift in epistemological positions, he has never abandoned basic physical realism; in all his works he has emphasized the statement that physical objects, however they are known, still exist when we are not aware of them.

Principles of Mathematics, 1903, 1948; Principles of Mathematica, 1910–1913 (co-authored with Whitehead); Philosophical Papers, 1910; Philosophical Problems, 1911; The Scientific Method in Philosophy, 1914 (also published in 1914 under the title Our Knowledge of the External World); Mysticism and Logic, 1918; Introduction to the Philosophy of Mathematics, 1919; Analysis of the Mind, 1921; Analysis of Matter, 1927; Philosophy, 1927; Collected Skeptical Papers, 1928; My Faith, 1929; Scientific Worldview, 1931; Religion and Science, 1935; The Search for Truth and Meaning, 1940; Philosophy and Political Science, 1947; Knowledge of Man, 1948; Authority and the Individual, 1949.

Russell's Philosophy, edited by p.a. Schilpp, vol. V, in Living Philosophers Series, 1941.