Propositions are truth-functions of elementary propositions. (An elementary proposition is a truth-function of itself.) 5.1 (01+5)    The truth-functions can be ordered in series. That is the foundation of the theory of probability. 5.2 (5)    The structures of propositions stand to one another in internal relations. 5.3 (2)    All propositions are results of truth-operations on the elementary propositions. The truth-operation is the way in which a truth-function arises from elementary propositions. According to the nature of truth-operations, in the same way as out of elementary propositions arise their truth-functions, from truth-functions arises a new one. Every truth-operation creates from truth-functions of elementary propositions, another truth-function of elementary propositions i.e. a proposition. The result of every truth-operation on the results of truth-operations on elementary propositions is also the result of one truth-operation on elementary propositions. Every proposition is the result of truth-operations on elementary propositions. 5.4 (7)    Here it becomes clear that there are no such things as 'logical objects' or 'logical constants' (in the sense of Frege and Russell). 5.5 (03+5)    Every truth-function is a result of the successive application of the operation  (- - - - -T) (,....)  to elementary propositions. This operation denies all the propositions in the right-hand bracket and I call it the negation of these propositions. 5.6 (4)    The limits of my language mean the limits of my world.