idea he interprets this particular situation. The movement of his thought is deductive. But it is not reflectively so; for he does not reflectively utilize the ground of his inference, or bring it forth explicitly from the background of his consciousness. The concept is, however, applied and determines both his thought and his action. The fisherman sees a pool in the stream which has certain well-marked characteristics familiar to him whereby he instantly infers that it is a good place to cast his line for fishing. There is a ground, or reason, for his expectation, but that reason may not operate reflectively. My general notions of courtesy, of business honesty, of reverence in church, etc., may determine my thought and my action in a thousand details. In every one of these cases there is doubtless a reason which could be pointed out, but as a matter of fact that reason operates quite unreflectively. There is the application of the concepts, their use in guiding and controlling both thought and action. In other words, there is a deductive process, but that deductive process is unreflective in character.

7. REFLECTIVE DEDUCTION, DEDUCTIVE METHOD.

We may say of deductive method, as we did of inductive method, that it is not a pure invention of the scientist and the logician. They have merely made explicit what is everywhere implicit in the use of accepted general notions to control thought and action. It is the characteristic of deduction as a method to make explicit the ground of all inferences. The specific device of deductive method for the reflective control of the whole process is the syllogism. The discussion of this is deferred until a later chapter.

Deduction, we have said in an earlier place, operates within a system of already organized knowledge. This does not mean that every part of that system is perfectly clear and explicit. Deduction operates within the system to clear it up and bring to light many things of which we were not

conscious and which we could not be said to know. There are two characteristic aspects of inductive_method: one the explanatory, the other the anticipatory. The explanatory aspect of deductive method takes some fact that belongs to a system and gives a reason for it, or justifies the fact on the basis of what we know about the principle of organization of the system to which the fact belongs. A few illustrations will make this plain. Here is a particular region in western Colorado. We find that it is dry and unproductive. Why? Because the moisture-laden winds from the Pacific ocean in crossing the Rocky mountains rise into higher altitudes, cool off, and deposit their moisture before they descend to the eastern side of the mountain chain. Here the isolated fact is explained by reference to a principle which applies to the whole system of facts to which it belongs. We call Florida a peninsula. Why? Because it is a portion of land nearly surrounded by water, and connected with a larger portion by a neck, or isthmus. The word James is a proper noun. Why? Because it is the name of a person. Six eighths equals three fourths. Why? Because when both terms of a fraction are divided by the same number the value of the fraction is unchanged. Here facts are justified by reference to controlling principles of the organized systems to which they belong.

Deductive method may be concerned also with the anticipation, or discovery, of facts which we do not know. I may not know that western Colorado is dry, but I may know that moisture-laden winds which pass over high mountains deposit their moisture on the near slope. Looking up western Colorado on the map, I find that it belongs to a system of geographical fact in which the ocean breezes are intercepted by a high range of mountains. I anticipate, then, or infer, that western Colorado will have a dry climate. This anticipation can be verified by actual observation or by consulting an authority of some sort. I have a triangle all of whose sides are of the same length. Here

a part of a system of fact is given. By the proper use of certain principles which have already been established, from this data I can discover the fact that the angles of this triangle are all equal. The inherent relationships within the system of geometric fact are such that I can pass from one part of the system deductively to another by means of certain general truths already proved or given by definition or construction. Knowing that in the American Revolution at a certain period the British have determined to separate the colonists into two groups which cannot assist each other, and knowing the details of the colonial life at that time, I can anticipate what the British plan of campaign will be. Of course they will seize upon the Hudson river valley as the strategic point of their campaign. Reading up on the subject, I find my inference to be correct. In every department of life, whether that of school study or that of practical affairs, organized knowledge may be used to anticipate or discover something more. tive method makes explicit the steps of inference throughout the whole process by which these anticipations, or discoveries, are attained. The grounds of all inferences are brought out, the reasons are stated.

Deduc

8. PEDAGOGICAL IMPORTANCE OF DEDUCTIVE METHOD.

Inductive method has received relatively more attention from the teaching profession for some time than deductive method. Deductive method has fallen into disgrace because of its abuse on the formal side. But there is a normal and natural place in instruction for deductive method. The goal of instruction is not the attainment of general notions, -of class concepts and laws, but the power to use them in controlling experience. Deduction is, after all, the practical side of thinking. The child needs training in deductive processes as well as in inductive. There is abundant opportunity without degenerating into formalism to employ the principle of deduction in both its explanatory and in its

anticipatory aspect in every school subject. Most interesting development lessons involving the anticipatory type of deduction can be worked out, as has been hinted at above, in geography, in history, and in mathematics. In using his organized body of knowledge to control thought processes which shall yield additional knowledge, the organization of fact itself becomes more definite and clear, and the concepts and laws which the pupil has become freer and more flexible tools of the mind in the control of experience.

9. SIGNIFICANCE OF INDUCTIVE AND DEDUCTIVE METHOD FROM THE POINT OF VIEW OF CONTROL.

It is evident that induction and deduction, when the processes are of the reflective type, represent highly organized and controlled methods of procedure in thinking. As methods which have been worked out and mastered so that they are the permanent property of the individual, they become, as it were, complex and very powerful tools for him,-tools which he may use in guiding and directing his thought processes to make them accomplish his purposes more efficiently. All the organized methods of doing business which the merchant has mastered are special elements of technique, or tools, which he employs to facilitate his business and give him added control over its problems. In like manner, organized methods of thinking, like induction and deduction, become powerful mental tools which facilitate the business of thinking and make the control of its problems more complete and adequate. From the biological point of view, this added power of the thought process means added power in the control which the individual is capable of exercising over every phase of his environment.

1Cf. Bagley, The Educative Process, Chapter XX.

INDUCTION AND DEDUCTION VIEWED AS

TECHNIQUE OF THINKING

(CONTINUED)

1. THE SPECIAL DEVICE OF DEDUCTIVE METHOD,-THE SYLLOGISM.

(1) General relation of the syllogism to deduction.

It is usually considered that the syllogism is the specific and characteristic element of technique in deductive thinking. This is true in so far as deduction is not made fully explicit except as it involves a process of verification, or proof, in which the ground, or reason, for each inference or transition in thought is explicitly pointed out. The syllogism is the special device for making sure that deduction is correct. It is always a phase of fully reflective deduction. But to describe even reflective deduction wholly in terms of an analysis of the syllogism, important as the device may be, would be to describe it in terms of an analysis of the finished product only and to ignore the dynamic side of the process. There is, as we pointed out in our illustration of geometric demonstration, even in reflective deductive thinking, a very large amount of tension and strain of the mind in the process of searching for and evaluating facts relevant to the solution of the problem. Connections of thought have to be made at the cost of much struggle and stress of mind. These connections of thought are exhibited in the formal demonstration only after they have been made.

(2) Illustration.

Under ordinary conditions, if I were traveling through the woods, and, while hungry and thirsty, came upon some