Zettel collects fragments from Wittgenstein's work between 1929 and 1948 on issues of the mind, mathematics, and language.

The Tractatus Logico-Philosophicus (Latin for "Logical-Philosophical Treatise") is the only book-length philosophical work published by the Austrian philosopher Ludwig Wittgenstein in his lifetime. It was an ambitious project: to identify the relationship between language and reality and to define the limits of science.