Page:The Story of Philosophy.pdf/92
68
THE STORY OF PHILOSOPHY
lescent Europe to reasoning and subtlety, constructed the terminology of modern science, and laid the bases of that same maturity of mind which was to outgrow and overthrow the very system and methods which had given it birth and sus¬ tenance. Logic means, simply, the art and method of correct think¬ ing. It is the logy or method of every science, of every dis¬ cipline and every art; and even music harbors it. It is a science because to a considerable extent the processes of cor¬ rect thinking can be reduced to rules like physics and geom¬ etry, and taught to any normal mind; it is an art because by practice it gives to thought, at last, that unconscious and immediate accuracy which guides the fingers of the pianist over his instrument to effortless harmonies. Nothing is so dull as logic, and nothing is so important. There was a hint of this new science in Socrates’ maddening insistence on definitions, and in Plato’s constant refining of every concept. Aristotle’s little treatise on Definitions shows how his logic found nourishment at this source. “If you wish to converse with me,” said Voltaire, “define your terms.” How many a debate would have been deflated into a paragraph if the disputants had dared to define their terms! This is the alpha and omega of logic, the heart and soul of it, that every important term in serious discourse shall be subjected to strictest scrutiny and definition. It is difficult, and ruth¬ lessly tests the mind; but once done it is half of any task. How shall we proceed to define an object or a term? Aristotle answers that every good definition has two parts, stands on two solid feet: first, it assigns the object in question to a class or group whose general characteristics are also its own—so man is, first of all, an animal; and secondly, it in¬ dicates wherein the object differs from all the other members in its class—so man, in the Aristotelian system, is a rational animal, his “specific difference” is that unlike all other ani¬ mals he is rational (here is the origin of a pretty legend). Aristotle drops an object into the ocean of its class, then takes