 The term ‘logic’ was understood in Bolzano’s time, as also by Bolzano himself, not in the narrow sense of formal logic, as it is commonly used nowadays, but rather in the broad sense which includes — besides formal logic — also both epistemology and the philosophy of science. Thus Bolzano used instead of ‘logic’ also the term ‘theory of science’. By ‘logic’ or ‘theory of science’ Bolzano means that discipline or science which formulates rules, “according to which we must proceed in the business of dividing the entire realm of truth into single sciences and in the exposition thereof in special textbooks if we want to proceed in a truly expedient fashion” (WL I, 7; cf. also WL I, 19 and 56).