INDUCTION (from

See also:

• LAT

Lat. inducere, to

See also:

• LEAD
• LEAD (pronounced iced)

lead into; cf. Gr. ilrayu yli)  , in logic, the term applied to the process of discovering principles by the observation and combination of particular instances . Aristotle, who did so much to establish the laws of deductive reasoning, neglected induction, which he identified with a complete enumeration of facts; and the schoolmen were wholly concerned with syllogistic logic . A new era opens with Bacon, whose writings all preach the principle of investigating the laws of nature with the purpose of improving the conditions of human life . Unluckily his mind was still enslaved by the formulae of the quasi-mechanical scholastic logic . He supposed that natural laws would disclose themselves by the accumulation and due arrangement of instances without any need for original speculation on the part of the investigator . In his Novum Organum there are directions for drawing up the various kinds of lists of instances . For two hundred years after Bacon's death little was done towards the theory of induction; the reason being, probably, that the practical scientists knew no logic, while the university logicians, with their conservative devotion to the syllogism, knew no science . Whewell's Philosophy of the Inductive Sciences (184o), the work of a thoroughly equipped scientist, if not of a great philosopher, shows due appreciation of the cardinal point neglected by Bacon, the function of theorizing in inductive research . He saw that science advances only in so far as the mind of the inquirer is able to suggest organizing ideas whereby our observations and experiments are colligated into intelligible system . In this respect J . S . Mill is inferior to Whewell: throughout his System of Logic (1843) he ignores the constitutive work of the mind, and regards knowledge as the merely passive reception of sensuous impressions .

His work was intended mainly to reduce the

procedure of induction to a regular demonstrative system like that of the syllogism; and it was for this purpose that he formulated his famous Four Methods of Experimental Inquiry . His work has contributed greatly to the systematic treatment of induction . But it must be remarked that his Four Methods are not methods of formal proof, as their author supposed, but methods whereby hypotheses are suggested or tested . The .actual proof of an hypothesis is never formal, but always lies in the tests of experiment or observation to which it is subjected . The current theory of induction as set forth in the standard works is so far satisfactory that it combines the merit of Whewell's treatment with that of Mill's; and yet it is plain that there is much for the logician of the future to accomplish . The most important faculty in scientific inquiry is the faculty of suggesting new and valuable hypotheses . But no one has ever given any explanation how the hypotheses arise in the mind: we attribute it to " genius," which, of course, is no explanation at all . The logic of discovery, in the higher sense of the term, simply has no existence . Another important but neglected province of the subject is the relation of scientific induction to the inductions of everyday life . There are some who think that a study of this relation would quite transform the accepted view of induction . Consider such a piece of reasoning as may be heard any day in a court of justice, a detective who explains how in his opinion a certain burglary was effected . If all reasoning is either deductive or inductive, this must be induction .

And yet it does not

answer to the accepted definition of induction, " the process of discovering a general principle by observation of particular instances ": what the detective does is to reconstruct a particular crime; he evolves no general principle . Such reasoning is used by every man in every hour of his life: by it we understand what people are doing around us, and what is the meaning of the sense-impressions which we receive . In the logic of the future it will probably be recognized that scientific induction is only one form of this universal constructive or reconstructive faculty . Another most important question closely akin to that just mentioned is the true relation between these reasoning processes and our general life as active intelligent beings . How is it that the detective is able to understand the burglar's plan of action?—the military commander to forecast the enemy's plan of campaign ? Primarily, because he himself is capable of making such plans . Men as active creatures co-operating with their fellow-men are incessantly engaged in forming plans and in apprehending the plans of those around them . Every plan may be viewed as a form of induction; it is a scheme invented to meet a given situation, an hypothesis which is put to the test of events, and is verified or refuted by practical success or failure . Such considerations widen still farther our view of scientific induction and help us to understandits relation to ordinary human thought and activity . The scientific investigator in his inductive stage is endeavouring to make out the plan on which his material is constructed . The phenomena serve as indications to help him in framing his hypothesis, generally a guess at first, which he proceeds to verify by experiment and the collection of additional facts . In the deductive stage he assumes that he has made out the plan and can apply it to the discovery of further detail .

He has the capacity of detecting plans in nature because he is wont to form plans for practical purposes . There are

good recent accounts of induction in Welton's Manual of Logic, ii., in H . W . B . Joseph's Introduction to Logic, and in W . R . Boyce Gibson's Problem of Logic; see also Lock . (H .