Bertrand Russell

This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.

Bertrand Russell's most famous discovery is, in a sense, a discovery about failure. Working on the foundations of mathematics in 1901, Russell found that a system very like Frege's, one that let any well defined property have a corresponding class, permitted a description of the class of all classes that are not members of themselves, and that description could not consistently be said either to belong to itself or not. This is Russell's Paradox, and the Stanford Encyclopedia's account of his career treats its discovery as the hinge of everything that follows in his logical work. Having broken the system he was extending, Russell then spent years constructing its replacement, the theory of types, which blocks the paradox by ranking every expression to a logical level and forbidding a class from being a member of itself or of anything at its own level or below. It is a solution that works, but the entry is candid that it never stopped being controversial. Both versions Russell produced, the simple theory and the more elaborate ramified theory he needed for his later work with Alfred North Whitehead, came under attack from opposite directions, the simple theory for being too weak to block every paradox and the ramified theory for being so strong that it made even reputable mathematics awkward to state. Russell's own fix to that overreach, the Axiom of Reducibility, struck many readers, then and now, as an admission that the theory of types worked only by grafting on an assumption with no independent justification beyond making the arithmetic come out right.

The same restless quality shows up away from logic. Russell's theory of descriptions, his analysis of phrases like the present King of France, is often presented as a piece of settled technical elegance, and the Stanford entry credits it as such, since the phrase is not a name that fails to refer but an incomplete symbol that only gets a meaning once folded into a full sentence, so that a sentence like the present King of France is bald comes out false rather than meaningless. But this same restlessness appears in Russell's readiness to abandon positions once he judged the arguments had turned against him. He gave up his early Kantian idealism once he decided the doctrine of internal relations could not be sustained, and he abandoned his multiple relation theory of judgment after Wittgenstein's criticism of it in 1913 convinced him it could not be repaired, a reversal that the entry treats as opening the path to his later neutral monism, the view that mind and matter are not two substances but two ways of organizing one and the same neutral material. Few major philosophers revised their own systems this openly, in public, in response to a specific interlocutor's objection.

The entry closes on a genuinely open dispute rather than a settled verdict, over how to weigh Russell's technical achievements in logic against the more troubling record of his later political and social writing, which touched on eugenics and included a proposal, later disavowed, for threatening nuclear force against the Soviet Union before it acquired its own weapons. Some readers treat the political Russell as a detachable embarrassment, irrelevant to assessing the logician. Others, citing commentators such as Alan Wood, argue that Russell's suspicion of unchecked power traces back to the same anti monist instincts that shaped his metaphysics, so that the politics and the philosophy are not separable after all. The Stanford Encyclopedia does not resolve this, and that refusal is itself part of what makes Russell's legacy still being argued rather than filed away.

This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.

Bertrand Russell's distinction between knowledge by acquaintance and knowledge by description, worked out most fully in a 1910 to 1911 paper of that title and repeated a year later in The Problems of Philosophy, was meant to answer a question that had troubled him since his break with idealism, namely what a mind can know without the mediation of inference. Acquaintance, in Russell's technical sense, is a direct cognitive relation to an object, a case in which the mind is directly aware of the object itself with nothing standing between the knower and the thing known. He restricted genuine acquaintance to a narrow class of items, chiefly the sense data of the present moment, such as the particular patch of color or the sound one is hearing right now, along with universals like whiteness or diversity, and, more controversially, oneself. What one is acquainted with, Russell stressed, is not a truth about the object but the object itself, so acquaintance is knowledge of things rather than knowledge of truths.

Almost everything else we claim to know, however, we know only by description. Description based knowledge concerns objects that are not themselves given to the mind but are picked out indirectly, through a definite description built from concepts and relations the mind is acquainted with. Russell's stock example contrasts Scott the man, whom his contemporaries might know directly, with the phrase the author of Waverley, which specifies an individual uniquely by a relation to a book without putting the mind in direct contact with the person. One can know a great many truths about the author of Waverley, including that he wrote a particular novel, without ever having met him, so long as one grasps the descriptive phrase and knows, or can verify, that exactly one thing satisfies it.

This distinction dovetailed with the theory of definite descriptions Russell had already developed in logic, in the earlier paper On Denoting, where he had shown that a phrase like the present King of France need not name an entity in order to be meaningful. Analyzed logically, the sentence the present King of France is bald asserts that there exists an x such that x is a present king of France, that x is the only such thing, and that x is bald. Since no such x exists, the sentence comes out false rather than meaningless or committed to a nonexistent king. Knowledge by description exploits exactly this structure, to know an object by description is to know that some unique thing satisfies a given descriptive condition, built entirely from concepts one is acquainted with, without the object itself ever being presented to the mind.

Russell treated this apparatus as the foundation of a genuinely empiricist epistemology, one meant to reduce every legitimate belief, in principle, to a chain terminating in items of direct acquaintance. He put the guiding principle bluntly, that every proposition we can understand must be composed wholly of constituents with which we are acquainted, since otherwise we could not grasp what the proposition asserted at all. Bismarck himself, as a historical agent known to us only through testimony and record, becomes an object known by description, built out of sense data, memories, and other people's acquaintance, rather than an object anyone alive today could claim direct acquaintance with.

This fed directly into the logical atomism of Russell's middle period, the view that the world ultimately consists of atomic facts, simple particulars standing in simple relations, mirrored by atomic propositions whose truth or falsity depends on how those facts stand. The acquaintance relation supplied the epistemological anchor for that ontology, since only what could be encountered directly, sense data and universals given in experience, counted as a genuine simple, while everything more complex, other minds, enduring physical objects, historical figures, had to be reconstructed as a logical description built out of those simples. Russell's own regressive method acknowledged a complication in this picture, that we often trust premises because we already trust their consequences rather than the reverse, yet he never abandoned the conviction that understanding has to bottom out somewhere in direct contact with what is known, and acquaintance was his name for that bottom.