The structure of the Tractatus is marked by its system of numbering; this system indicates assumptions, definitions, summaries, consequences, each of various kinds. Some grasp of the structure of the Tractatus is useful for several reasons. It can help the reader to avoid becoming lost in details before he has seen the general philosophical point which the details are meant to be clarifying. Secondly, what the Tractatus says about one subject is often significant because it has been deduced from elsewhere, rather than because of superficial plausibility, so that unless the connections between the various claims of the book are seen, those claims are likely to appear disjointed, aphoristic, and obscure. And thirdly, the structure of the Tractatus is important for philosophical method, because it makes clear what are the major axioms and theorems of the metaphysics, and hence where attention should be directed, should we need to reject any or all of that metaphysics.