Logical Atomism

The claim

The world is the totality of facts, not of things. Complex propositions are truth-functions of atomic ones, and atomic propositions correspond to atomic facts that are logically independent of each other.

What it held

Logical atomism is metaphysics read off from logic. If the new quantificational logic is the right way to analyse propositions, and if every complex proposition is built from simple ones, then a fully analysed language would end in simple propositions — and if language pictures the world, the world must end in simple facts.

Wittgenstein's Tractatus is the more austere version. A proposition is a picture of a possible state of affairs, sharing its logical form; that is why it can say something. But the relation of picturing cannot itself be pictured, so the most important things — logical form, ethics, the sense of the world — cannot be said. His last proposition tells the reader to be silent about them, and the penultimate says the whole book is nonsense to be discarded once climbed.

Russell's version is looser and more empirical, with sense-data as the atoms.

The programme collapsed on a detail. Two colour statements about the same point — this is red, this is blue — cannot both be true, yet on the theory atomic propositions must be independent. Wittgenstein noticed, could not repair it, and it was one of the things that brought him back to philosophy.

How it argued

Analysis of propositions into truth-functional combinations of atomic propositions, with the structure of language taken as evidence about the structure of the world.

What it was arguing against

Idealist holism, and the notion that a proposition's grammatical form tells you anything about its logic.

Where it disagreed with itself

What the atoms are — Russell said sense-data, Wittgenstein never said. Whether the Tractatus is a metaphysics or a demonstration that metaphysics cannot be stated.

Common misconceptions

That the Tractatus asserts a positive metaphysics. Its own penultimate proposition says the reader must throw away the ladder, and how seriously to take that is the central interpretive question about the book.

How it began

Russell's 1918 lectures, delivered while facing prosecution for his opposition to the war, and Wittgenstein's Tractatus, written partly in the trenches and in an Italian prison camp.

What became of it

Abandoned by both its authors. Wittgenstein returned to Cambridge and demolished it himself in the Philosophical Investigations.

Lasting influence

The Vienna Circle took the Tractatus as founding. Its failure is what produced ordinary language philosophy, which was a reaction against it.

Why it still matters

The colour-exclusion problem is a nice case of a theory brought down by an ordinary fact, and truth-functional analysis remains basic logic.

Put another way

A model of a car accident made with toy cars, which works because the arrangement can mirror the arrangement.

Where to start

Russell's lectures. The Tractatus without a guide is a wall.

The surprising bit

Wittgenstein believed he had solved all the problems of philosophy, gave away his considerable inherited fortune, and went to teach primary school in rural Austria.

In their own words

Connections

Answers

Cambridge Analysis

Opposed by

British Idealism

Influenced

Vienna Circle, Ordinary Language Philosophy

The verdict

A theory abandoned by both of its inventors, which nevertheless set the agenda for thirty years.

Sources

• Stanford Encyclopedia of Philosophy