 Theophrastus also considered relative quantified propositions such as those containing “more”, “less” and “equal”, and seems to have considered syllogisms built from such premises (fr. 111E FHS&amp;G). But however innovative his additions to Aristotle’s syllogistic may have been, Theophrastus’ hypothetical syllogisms cannot be said to form part of an elaborate and comprehensive system of propositional logic, and thus he cannot be credited with the invention of a logical calculus similar to that of the Stoics.