This treatise, in its first part, moves from a consideration of behaviour and utterance through a definition of assertion as a kind of utterance to a consideration of statements, conceived of as products of assertion, to be represented by pairs of testing procedures of verification and falsification. The treatise, in its second part, identifies a small number of basic forms of testing procedures, affiliated to the "syncategoremata" of classical philosophy, and uses these to represent all distinguishable, humanly producible, forms of statement. This same apparatus is used, in the third part of the treatise, to explain our conception of an object of reference and of various constructions from such objects. Particular attention is given to bodies and to other things met with in space and time, where it is finally argued that bodies, as we have explained them, are our most fundamental objects of reference.
