The Preface to the Tractatus mentions Wittgenstein's two main intellectual debts in the famous words, "I am indebted to Frege's great works and to the writings of my friend Mr. Bertrand Russell for much of the stimulation of my thought." (TLP,p. 3) The evaluative nuance is unmistakable. Wittgenstein's personal debt to Russell was of course inestimable, and I would judge his intellectual debt to Russell was also greater than to Frege. To chart the intricacies of the relationship between the views of Russell and those of Wittgenstein would require a monograph. The influences and interactions in the case of Frege are of more manageable extent, though they also penetrate Wittgenstein's whole conception of logic. I shall talk about two things only: firstly, the personal relationship between Wittgenstein and Frege, especially in the light of the recently discovered correspondence, and secondly, Wittgenstein's criticism of Frege's theory of truth and negation, which is the core of his attack on Frege's conception of logic. There are many other aspects of Wittgenstein's views on Frege which I shall not touch, but I think those I mention are among the most important.