Logic, however, did not begin as a science of all inference. Rather it began as a science of reasoning ([Greek: logos]), of syllogism ([Greek: syllogismos]), of deductive inference. Aristotle was its founder. He was anticipated of course by many generations of spontaneous thinking (_logica naturalis_). Many of the higher animals infer by analogy: otherwise we cannot explain their thinking. Man so infers at first: otherwise we cannot explain the actions of young children, who before they begin to speak give no evidence of universal thinking. It is likely that man began with particular inference and with particular language; and that, gradually generalizing thought and language, he learnt at last to think and say "all," to infer universally, to induce and deduce, to reason, in short, and raise himself above other animals. In ancient times, and especially in Egypt, Babylon and Greece, he went on to develop reason into science or the systematic investigation of definite subjects, e.g. arithmetic of number, geometry of magnitude, astronomy of stars, politics of government, ethics of goods. In Greece he became more and more reflective and conscious of himself, of his body and soul, his manners and morals, his mental operations and especially his reason. One of the characteristics of Greek philosophers is their growing tendency, in investigating any subject, to turn round and ask themselves what should be the method of investigation. In this way the Presocratics and Sophists, and still more Socrates and Plato, threw out hints on sense and reason, on inferential processes and scientific methods which may be called anticipations of logic. But Aristotle was the first to conceive of reasoning itself as a definite subject of a special science, which he called analytics or analytic science, specially designed to analyse syllogism and especially demonstrative syllogism, or science, and to be in fact a science of sciences. He was therefore the founder of the science of logic. Among the Aristotelian treatises we have the following, which together constitute this new science of reasoning:-- 1. The _Categories_, or names signifying things which can become predicates; 2. The _De Interpretatione_, or the enumeration of conceptions and their combinations by (1) nouns and verbs (names), (2) enunciations (propositions); 3. The _Prior Analytics_, on syllogism; 4. The _Posterior Analytics_, on demonstrative syllogism, or science; 5. The _Topics_, on dialectical syllogism; or argument; 6. The _Sophistical Elenchi_, on sophistical or contentious syllogism, or sophistical fallacies.