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. Both transform the identity of thinking and being first formulated by Parmenides “... to gar auto noein estin te kai einai“ (D/K.B3