The tree of the Tractatus, a true cognitive map, puts every argument at its place into the general plan of the work. If we read the book by succeeding stages of analysis, we can realise that the controversial section 5.6, about the ego and limits of lan- guage and world, is the factual outcome of commentary 5.1-5.6 on "truth-function". The way in which "logic fills the world" leads to the suggestion that "solipsism coincides with pure realism" (path 5.61-5.64); the elimination of an empirical "I" results in the abolition of all a priori forms of our experience - and of any a priori, indeed, outside logics (5.631-5.634); nor does the form of the visual field suggest the need of an observing eye (5.6331). In its last part, the article shows the original drawing of 5.6331 diagram and demonstrates how it was badly read and worse edited and reproduced. Because of its central role in usual readings of the whole section, this implies a substantial review of most of the traditional exegeses.
Keywords: Logical apriori, Self, Tractatus, Tree, Truth-function, Wittgenstein.