Perhaps the simplest way of disentangling the leading features of the departments of Logic is to take them in relation to historical circumstances. These features are writ large, as it were, in history. If we recognise that all bodies of doctrine have their origin in practical needs, we may conceive different ages as controlled each by a distinctive spirit, which issues its mandate to the men of the age, assigning to them their distinctive work.
The mandate issued to the age of Plato and Aristotle was Bring your beliefs into harmony one with another. The Aristotelian Logic was framed in response to this order: its main aim was to devise instruments for making clear the coherence, the concatenation, the mutual implication of current beliefs.
The mandate of the Mediæval Spirit was Bring your beliefs into harmony with dogma. The mediæval logic was contracted from Aristotle's under this impulse. Induction as conceived by him was neglected, allowed to dwindle, almost to disappear from Logic. Greater prominence was given to Deduction.
Then as Dogmatic Authority became aggressive, and the Church through its officials claimed to pronounce on matters outside Theology, a new spirit was roused, the mandate of which was, Bring your beliefs into harmony with facts. It was under this impulse that a body of methodical doctrine vaguely called Induction gradually originated.
In dealing with the genesis of the Old Logic, we began with Aristotle. None can dispute his title to be called its founder. But who was the founder of the New Logic? In what circumstances did it originate?
The credit of founding Induction is usually given to Francis Bacon, Lord Verulam. That great man claimed it for himself in calling his treatise on the Interpretation of Nature the Novum Organum. The claim is generally conceded. Reid's account of the matter represents the current belief since Bacon's own time.
"After man had laboured in the search of truth near two thousand years by the help of Syllogisms, [Lord] Bacon proposed the method of Induction as a more effectual engine for that purpose. His Novum Organum gave a new turn to the thoughts and labours of the inquisitive, more remarkable and more useful than that which the Organon of Aristotle had given before, and may be considered as a second grand era in the progress of human nature.... Most arts have been reduced to rules after they had been brought to a considerable degree of perfection by the natural sagacity of artists; and the rules have been drawn from the best examples of the art that had been before exhibited; but the art of philosophical induction was delineated by [Lord] Bacon in a very ample manner before the world had seen any tolerable example of it."[1]
There is a radical misconception here, which, for reasons that I hope to make plain, imperatively needs to be cleared up. It obscures the very essence of "philosophical induction".
There are three ways in which movement in any direction may be helped forward, Exhortation, Example, and Precept. Exhortation: a man may exhort to the practice of an art and thereby give a stimulus. Example: he may practise the art himself, and show by example how a thing should be done. Precept: he may formulate a clear method, and so make plain how to do it. Let us see what was Bacon's achievement in each of those three ways.
Undoubtedly Bacon's powerful eloquence and high political position contributed much to make the study of Nature fashionable. He was high in place and great in intellect, one of the commanding personalities of his time. Taking "all knowledge for his province," though study was really but his recreation, he sketched out a plan of universal conquest with a clearness and confidence that made the mob eager to range themselves under his leadership. He was the magnificent demagogue of science. There had been champions of "Induction" before him, but they had been comparatively obscure and tongue-tied.