This paper was presented at the University of Illinois in the northern Spring of 1961. Its title is slightly misleading, as it deals more with influences on Wittgenstein than any particular influences he had on others. In particular, it points to an interesting indirect influence the philosophy of C.S. Peirce on Wittgenstein’s later thought – an of inflluence that came about as a result of the many philosophical interactions between Wittgenstein and Frank Ramsey, who was much impressed by Peirce’s work. (...) -/- The paper provides a sympathetic outline of the development of Wittgenstein’s thought, discussing such central topics as the general nature of language, proofs, and rule following. It concludes with a clear exposition of Wittgenstein’s “private language argument”. (Tim Oakley, March 2019). (shrink)