Tractatus Logico-Philosophicus: What It Is and What It Says

What the Tractatus Logico-Philosophicus is

According to the Stanford Encyclopedia of Philosophy, the Tractatus Logico-Philosophicus first appeared in German in 1921; the following year came C.K. Ogden’s English translation, made with the collaboration of F.P. Ramsey. The Internet Encyclopedia of Philosophy calls it the only philosophy book Ludwig Wittgenstein published during his lifetime. The work presented itself as a solution to the major problems of philosophy, and the same source notes that it was held in high esteem by the logical positivists, despite their openly anti-metaphysical stance.

The Tractatus marks the first stretch of Wittgenstein’s philosophical path, from the early work on logic to his later thought on ordinary language.

The picture theory of language

The heart of the book is the picture theory. A proposition works as a model of reality, made up of elements that together constitute it. That picture’s structure — whether it lives in thought or in language — matches point for point how the state of affairs it depicts is itself put together; it is this shared structure, according to the Tractatus, that connects the picture to reality. The world and thought share with the proposition the same logical form, and this is the condition that lets thought, in the shape of a proposition, represent the world. The Internet Encyclopedia of Philosophy uses a similar image, calling a proposition a picture of reality.

Practical example: a proposition like “the book is on the table” works, in the logic of the Tractatus, as a small model. The words of the proposition combine with each other the way the book and the table combine in reality: if the arrangement of the words matches the actual arrangement of the objects, the proposition is true; otherwise it is false. It is the structure that ties the sentence to the world, not the isolated meaning of each single word.

The world as a totality of facts

The question of what the world is, and how language can speak of it, did not begin with Wittgenstein: the logic of Aristotle and the debates of scholastic philosophy had already raised it, in different terms. The Tractatus takes it up from a new angle, centered on the relationship between language and reality.

The book’s opening proposition, in the Ogden/Ramsey translation available on The Wittgenstein Project, defines the world as everything that is the case, that is, the totality of existing facts. The world, for Wittgenstein, is thus the totality of facts. The book adds that states of affairs are combinations of simple objects, which can nonetheless combine with each other in various determinate ways: the same handful of objects, arranged differently, produces different states of affairs.

For Wittgenstein, it is the proposition as a whole that has sense, and a name taken on its own has meaning only within the context of a proposition: isolated from any sentence, it signifies nothing definite.

Saying and showing: the limit of language

The book distinguishes between what language can say explicitly and what can only show itself through its logical form: propositions display the logical form of reality, the Internet Encyclopedia of Philosophy explains, rather than describing it as further content. For Wittgenstein, the limits of a person’s language coincide with the limits of their world: what cannot be said in a proposition with sense falls outside that world. The Tractatus identifies the set of true propositions with the whole of natural science and excludes from that domain ethics, aesthetics and metaphysics: subjects that remain outside the limits of what a proposition can say with sense.

The final proposition: silence beyond what can be said

In the Ogden/Ramsey translation, the book’s final proposition — number 7 — closes the work with an injunction to silence about everything that exceeds the limits of meaningful language. The Pears/McGuinness translation, in its own words, reaches the same point: it urges silence about what cannot be spoken of with sense.

It is the most quoted proposition in the Tractatus. It marks the limit beyond which the book itself, made of propositions about the world, stops being able to speak with sense.