Bertrand Russellís Theory of Knowledge (1913) is an analysis of the differences which may occur between various cognitive relations (such as attention, sensation, memory, and imagination), and is an explanation of how cognitive data (such as perceptions and concepts) may become elements of knowledge. Russell explains how knowledge may involve acquaintance with logical or empirical facts, and discusses the difference between acquaintance (as a dual relation between a subject and an object) and belief (as a multiple relation between a subject and a complex of objects). Russell also discusses the distinction between truth and falsehood, and explains the difference between direct and indirect knowledge (i.e. knowledge by acquaintance and knowledge by description).
An important question concerning the limits of knowledge is whether knowledge may be attained of things which are beyond our own personal experience. Russell argues that such transcendent knowledge is possible, because we may, in some cases, be able to describe things which we have not experienced, if we use terms which are within our own personal experience. Also, we may know, in some cases, that there are things which we have forgotten, even though we may not be able to name such things.
Another important question concerning the limits of knowledge is whether the nature of our experience is mental or physical. According to Russell, "materialistic monism" is the theory that all reality is physical, and that mental phenomena are merely rearrangements of physical matter. "Idealistic monism" is the theory that all reality is mental, and that the physical world is produced by the mind. "Neutral monism" is the theory that physical and mental reality are not intrinsically different, and that physical and mental phenomena are merely rearrangements of a single, neutral substance or element.
Russell criticizes "materialistic monism" for its assertion that every cognitive relation is physical, and for its assertion that there are no abstract facts. Russell criticizes "idealistic monism" for its assertion that we cannot experience the physical world directly and that we can only experience the physical world through the medium of "ideas." Russell criticizes "neutral monism" for its inability to determine whether sensory experience is mental or physical, and for its inability to distinguish what is mental from what is physical.
According to Russell, acquaintance is a basic cognitive relation and fundamental aspect of human experience. Acquaintance is a subject-object relation in which an object is experienced (perceived, reflected upon, remembered, or imagined) by a subject. Russell argues that there are no unreal objects of acquaintance. Illusory or imagined objects may be real objects of acquaintance. Imagination, as a relation of acquaintance, may be as real as sensation.
Russell argues that sensation is a relation of acquaintance with a particular object, and that the object of sensation is simultaneously present for the subject. Memory, on the other hand, is a relation in which a subject recalls a past acquaintance with a particular object. Imagination is a relation which, unlike sensation or memory, does not depend on any temporal relation between the subject and the object.
Russell explains that sensation and memory establish temporal relations between subject and object, while simultaneity and succession establish temporal relations between an object and another object. Past, present, and future are temporal relations between subject and object, while earlier and later are temporal relations between an object and another object.1 Knowledge of past objects may occur both by recall of past acquaintance and by present experience which demonstrates that the objects are in the past.
Russell also says that cognitive relations may include "atomic" or "molecular" complexes. An ďatomic complexĒ may consist of analyzable constituents, and may be expressed by a single proposition. A "molecular complex" may include multiple atomic complexes. A molecular complex cannot be expressed by a single proposition, but may be expressed by more than one proposition.2
Russell maintains that the constituents of atomic or molecular complexes may be particular or universal, but that at least one constituent of each complex must be universal.3 Universals may include predicates and relations. An atomic proposition may express an atomic complex, while a molecular proposition may express a molecular complex. None of the parts of an atomic proposition is a proposition, but at least one of the parts of a molecular proposition is a proposition.4
According to Russell, analysis of a complex may be formal, material, or complete. A formal analysis of a complex may describe how the constituents of the complex are arranged or combined. A material analysis of a complex may identify the constituents of the complex. A complete analysis of a complex may describe both the formal and material composition of the complex.
Russell explains that acquaintance with a complex of objects may not necessarily imply that the subject is aware of all the individual constituents of that complex. Furthermore, acquaintance with an object may not necessarily imply that the subject is aware of his or her own acquaintance with that object. The consciousness of a subject is not necessarily implied by the subjectís relation of acquaintance with an object.
Russell distinguishes between simple and complex perception as relations of acquaintance. Simple perception may be defined by attention to a complex of objects as a whole, while complex perception may be defined by attention to the interrelated parts of a complex. The process of analyzing a complex of objects may thus involve transferring attention from the whole complex to the parts of the complex.5
Russell supports a correspondence theory of truth, arguing that true beliefs about complexes of objects correspond to the complexes of objects as they are in reality. For a true belief, there is a corresponding complex of objects. For a false belief, there is no corresponding complex of objects.
True beliefs do not constitute knowledge until their truth becomes self-evident. The truth of a belief may become self-evident if its truth is evident without the need for any demonstration which is based on the evidence of other beliefs. According to Russell, knowledge is based on acquaintance with self-evident truths. True propositions which are not self-evident may have to be demonstrated to be true by self-evident propositions in order to become objects of knowledge. Knowledge is based on acquaintance with self-evident propositions and with propositions whose truth can be demonstrated by self-evident propositions.
Russell, Bertrand. Theory of Knowledge: The 1913 Manuscript. Edited by Elizabeth Ramsden Eames, in collaboration with Kenneth Blackwell. London: George Allen & Unwin, 1984.