Among historians of philosophy, there have been significant developments in our understanding of Russell’s logical atomism. But setting aside disagreements over the details, I think it may be said that the interpretation of logical atomism, which I describe below, remains the dominant view of logical atomism among professional philosophers. I here argue against the dominant interpretation.

By way of introduction, I start with common ground between the dominant interpretation and my own. Logical atomists do claim that “there are many separate things”:

The logic which I shall advocate is atomistic, as opposed to the monistic logic of the people who more or less follow Hegel. When I say that my logic is atomistic, I mean that I share the common-sense belief that there are many separate things; I do not regard the apparent multiplicity of the world as consisting merely in phases and unreal divisions of a single indivisible Reality. (PLA: 160)

Similarly, any atoms of logical atomism are, as the name suggests, logical and not physical:

The reason that I call my doctrine logical atomism is because the atoms that I wish to arrive at as the sort of last residue in analysis are logical atoms and not physical atoms. Some of them will be what I call “particulars”—such things as little patches of colour or sounds, momentary things—and some of them will be predicates or relations and so on. The point is that the atom I wish to arrive at is the atom of logical analysis, not the atom of physical analysis. (PLA: 161)

These two quotes from the beginning of Russell’s 1918 logical atomism lectures are jointly the focus of multiple influential scholarly commentaries on Russell’s lectures:

When they are true, atomic sentences stand for the simplest complex constituents of reality, which are facts consisting of objects named by logically proper names bearing the properties, and standing in the relations , designated by predicates. (Soames 2014: 577, see also 574)

Russell’s lectures on The Philosophy of Logical Atomism begin with an outline sketch of what he means by ‘logical atomism’: Its basic premise is that the world contains many different things, and that to find out what these things are we need to practise what he calls ‘analysis’. The idea is that almost all familiar things are in one or another way complex, but by analysis we can find out what simpler components these complex things are put together from, and if we continue this process we should end by reaching the ultimately simple things from which all else is composed. These are the ‘atoms’, and they are called ‘logical atoms’ because they are the last residue of ‘logical analysis’, which is said to be something quite different from physical analysis. (Bostock 2012: 252)

The ‘logical’ in the label signals that the atoms are arrived at as the ‘last residue of analysis’ where the analysis is logical rather than physical … Logical atomism is the view that in theory, if not in practice, analysis takes us down to the ultimate simples out of which the world is built. (Grayling 1996: 50–51)

Logical atomism … is a theory about the fundamental structure of reality and so it belongs to the main tradition of western metaphysics. Its central claim is that everything that we ever experience can be analyzed into logical atoms. [Pears then quotes Russell: “the atom I wish to arrive at is the atom of logical analysis”.] (Pears 1985: 1)

The basic thesis of logical atomism … was that the world consists of simple particulars which have only simple qualities and stand only in simple relations to one another. (Ayer 1972: 103–104)

I see here a pattern of taking the above two quotes from Russell’s lectures as statements of the essence, that is, the critical theses, of logical atomism. We should add to the above two quotes Russell’s views on a logically perfect language, and on acquaintance and meaning, which have led some to call logical atomism a “theory of meaning”:

In a logically perfect language the words in a proposition would correspond one by one with the components of the corresponding fact, with the exception of such words as “or”, “not”, “if”, “then”, which have a different function . In a logically perfect language, there will be one word and no more for every simple object, and everything that is not simple will be expressed by a combination of words, by a combination derived, of course, from the words for the simple things that enter in, one word for each simple component. (PLA: 176)

Soames , Urmson , and Pears state the dominant interpretation’s view of such statements:

It is a central aim of logical atomism to replace unanalyzed terms, predicates, and sentences-cum-propositions—which may stand in conceptual relations to one another—with logically proper names, simple unanalyzable predicates, and fully analyzed propositions. When this aim is achieved, the conceptual properties of, and relations holding among, unanalyzed expressions and sentences are traced to genuinely logical properties of, and relations holding among, fully analyzed propositions of the agent’s logically perfect language . (Soames 2014: 586)

The shortest account of logical atomism that can be given is that the world has the structure of Russell’s mathematical logic … The structure of the world would thus resemble the structure of Principia Mathematica. That is the simple argument of the plot . (Urmson 1956: 6–7)

[Logical atomism does] start from the assumption that there is a general correspondence between language and reality, which ensures that the complete analysis of words will match the complete analysis of things … The idea is that, when we analyze the words in our vocabulary, we soon reach a point at which we find that we cannot analyze them any further, and so we conclude that we have reached the bottom line where unanalyzable words correspond to unanalyzable things. (Pears 1985: 4–5)

The dominant interpretation of logical atomism thus emerges from an elegant synthesis of Russell’s views. That is, logical atomism on the dominant reading merges (1) an ontological pluralism on which there are multiple logically independent entities, (2) a theory of meaning on which the referents of predicates and names are logically simple and mean their objects, and (3) an acquaintance epistemology that guarantees both the reference of predicates and names, and the truth of fully analyzed sentences in a philosophically ideal language. To these doctrines is added (4) an analytic program that picks apart the meaning of logically complex ordinary words and traces their meaning to logically simple words. It is this interpretative synthesis that I describe as the reading of logical atomism as “a search for complexes composed of entities with which we have acquaintance”, or just “a search for acquaintance-complexes” for short.

This is the dominant reading of logical atomism. Some historians of philosophy reject this interpretation in its particulars, and some reject it in its essentials. Still, the widespread impression of logical atomism seems to be that it is essentially tied to Russell’s views on acquaintance and meaning, and to an ontology of logical atoms, or perhaps necessarily existing simples.

I argue the dominant interpretation with its correlated and widespread impression of logical atomism as bound up with Russell’s acquaintance epistemology is a misleading characterization of logical atomism. It is misleading because what is really crucial to logical atomism is logic. And not just any logic will do: a logical atomist needs a logic that is quite powerful, one at least that has expressive capacity sufficient to logically analyze and synthesize philosophical notions at least as complex as those of higher mathematics. A logical atomist also holds a certain view ab...