Abstract
The paper puts forward that the basic principle of Wittgenstein’s Tractatus (4.0312) transforms the supreme principle of all synthetic judgments a priori in Kant’s Critique of Pure Reason (A158/B197) from a level of reason to the level of language. Both philosophers, Kant and Wittgenstein, put forward a transcendental principle and both hold a formal identity true, Kant an identity between the form of experience and the form of the object of experience, Wittgenstein an identity between the form of a sentence and the form of a fact.