Crewe was an exponent of the deductive school of crime investigation, and had first achieved fame over the Abbindon case some years ago, when he had succeeded in restoring the kidnapped heir of the Abbindon estates after the police had failed to trace the missing child.

In detective stories the attitude of members of Scotland Yard to the deductive expert is that of admiration based on conscious inferiority, but in real life the experts of Scotland Yard have the utmost contempt for the deductive experts and their methods.

In detective stories the attitude of members of Scotland Yard to the deductive expert is that of admiration based on conscious inferiority, but in real life the experts of Scotland Yard have the utmost contempt for the deductive experts and their methods.

The disdainful pity of the deductive experts for the rule-of-thumb methods of the police is not to be compared with the vigorous scorn of the official detective for the rival who has not had the benefit of police training.

" Rolfe was so interested in Crewe's revelations that he stood beside the deductive expert and studied the paper afresh.

" "And what do you make of the disappearance of Sir Horace's revolver?" asked Rolfe, who seemed to his superior officer to be in danger of displaying some admiration for deductive methods.

He was not a deductive expert, and, as he told his wife afterwards, he did not know what the detective was "driving at."

By arithmetical calculation the chances that twelve men are wrong and twelve thousand right, on a matter of inductive or deductive proof, are found to amount to what must be taken for practical certainty; and when the twelve still hold out, they are regarded as madmen or knaves, and treated accordingly by their fellows.

Deductive reasoning is the pure syllogism which shows why a third proposition must necessarily result if two others are assumed, but which does not help us to determine whether the two initial statements are true or not.

The relation of the two modes of reasoning is that, first by observing a sufficient number of instances, we inductively reach the conclusion that a certain principle is of general application, and then we enter upon the deductive process by assuming the truth of this principle and determining what result must follow in a particular case on the hypothesis of its truth.

Thus deductive reasoning proceeds on the assumption of the correctness of certain hypotheses or suppositions with which it sets out: it is not concerned with the truth or falsity of those suppositions, but only with the question as to what results must necessarily follow supposing them to be true.

Now it is the deductive method only which is followed by the subjective mind.

Thus it would seem that among the ancients, in those departments of science which are inductive, there were not sufficient facts, well established, from which to make sound inductions; but in those departments which are deductive, like pure mathematics, and which require great reasoning powers, there were lofty attainments,which indeed gave the foundation for the achievements of modern science.

Then the inductive ascent from experiment to axiom is to be followed by a deductive descent from axioms to new experiments and discoveries.

This implies the equal validity of the deductive and inductive methods,while Bacon had proclaimed the latter the most important instrument of knowledge,as well as the exclusion of theology based on revelation from the domain of science.

Logic, deductive and inductive.

FITCH, FREDERIC B. Mathematico, deductive theory of rote learning.

Mathematico, deductive theory of rote learning.

SEE Edwards, Austyn R. HOVLAND, CARL I. Mathematico, deductive theory of rote learning.

HULL, CLARK L. Mathematico, deductive theory of rote learning; a study in scientific methodology, by Clark L. Hull, Carl I. Hovland, Robert T. Ross, Marshall Hall, Donald T. Perkins & Frederic B. Fitch.

HULL, RICHARD H. Mathematico, deductive theory of rote learning.

(In The New Yorker, July 20, 1940) © 18Jul40; B464082. S. J. Perelman (A); 7Nov67; R422062. PERKINS, DONALD T. Mathematico, deductive theory of rote learning.

SEE Ross, Ernest C. ROSS, ROBERT T. Mathematico, deductive theory of rote learning.

Logic, deductive and inductive.

CRUMLEY, THOMAS, ESTATE OF. Logic, deductive, and inductive.