ARISTOTLE TO AUGUSTINE It is indeed one of Aristotle’s many claims on posterity that he was logic’s founder His most important works on the subject are the Categories, the de Interpretatione, and the Prior Analytics These set out his teaching on simple terms, on propositions, and on syllogisms They were grouped together, along with the two works already mentioned, and a treatise on scientiWc method, the Posterior Analytics, into a collection known as the Organon, or ‘tool’ of thought Most of Aristotle’s followers thought of logic not as itself a scientiWc discipline, but as a propaedeutic art which could be used in any discipline; hence the title The Organon, though shown already in antiquity to be incomplete as a system of logic, was regarded for two millennia as providing the core of the subject.1 While Aristotle was at the Academy, King Philip II of Macedon, who succeeded his father in 359, adopted an expansionist policy and waged war on a number of Greek city-states, including Athens Despite the martial eloquence of Aristotle’s contemporary Demosthenes, who denounced the Macedonian king in his ‘Philippics’, the Athenians defended their interests only half-heartedly After a series of humiliating concessions they allowed Philip to become, by 338, master of the Greek world It cannot have been an easy time to be a Macedonian resident in Athens Within the Academy, however, relations seem to have remained cordial Later generations liked to portray Plato and Aristotle embattled against each other, and some in antiquity likened Aristotle to an ungrateful colt who had kicked his mother (D.L 1) But Aristotle always acknowledged a great debt to Plato, whom on his death he described as the best and happiest of mortals ‘whom it is not right for evil men even to praise’ He took a large part of his philosophical agenda from Plato, and his teaching is more often a modiWcation than a repudiation of Plato’s doctrines The philosophical ideas that are common to the two philosophers are more important than the issues that divide them—just as, in the seventeenth and eighteenth centuries, the opposing schools of rationalists and empiricists had much more in common with each other than with the philosophers who preceded and followed them Already, however, during his period at the Academy, Aristotle began to distance himself from Plato’s Theory of Ideas In his pamphlet On Ideas he maintained that the arguments of Plato’s central dialogues establish only Aristotle’s logic is considered in detail in Ch 68