The Logic of Demonstration

Abstract

While setting out the program of the Prior Analytics, Aristotle states that this treatise aims to inquire into demonstration and demonstrative knowledge (24a1–2). Concluding the Posterior Analytics, Aristotle recapitulates both Analytics: “It is clear now what syllogism and demonstration are and how they came about” (99b15–17). Aristotle seems to consider the theory of syllogism and the theory of demonstration a unitary whole, the former serving as an indispensable stage for developing the latter. Throughout the Posterior Analytics syllogistic inferences exemplify and elucidate the various features of demonstrative knowledge. For instance, in the second book of the Posterior Analytics the attainment of knowledge of the reason why is characterized as a search for a middle term; in the Posterior Analytics I.14 the first syllogistic figure is said to be the most suitable for attaining knowledge (epistêmonikon malista); and Aristotle’s distinction between knowledge of the fact and knowledge of the reason why is exemplified by syllogistic inferences. Generally, syllogistic inferences appear to be integral to the theory of demonstrative knowledge.