Abstract
I track the origin in Wittgenstein's work of Waismann's concept of open texture and compare their related ideas. Although Waismann published his work on open texture before the publication of Wittgenstein's Philosophical Investigations, he had access to drafts of that work and to other writings of Wittgenstein and heard him present related ideas. A key example of his is closely derived from Wittgenstein's work. We shall see advantages of Wittgenstein's ideas over Waismann's. Waismann does not satisfactorily distinguish semantic from epistemic points; he seems to think that drawing boundaries is done only by definitions; he unjustly sees open texture as the possibility of vagueness, which he problematically conceives as a fluctuating use of a word, and more. In all these respects, Wittgenstein is more precise in his characterisation of the idea. Accordingly, we better follow Wittgenstein in our use of the concept of open texture.