In the type of study involving reasoning, because of its complexity, and because the individual must work more independently, the child must learn the danger of following the first suggestion which offers itself. He must learn to weigh each suggestion offered with reference to the goal aimed at. Each step in the process must be tested and weighed in this manner. To go blindly ahead, following out a line of suggestions until the end is reached, which is then found to be the wrong one, wastes much time and is extremely discouraging. No suggestion of the way to adapt means to end should be accepted without careful criticism. The pupil should gradually be made conscious of the technique of reasoning, analysis, comparison, and abstraction. He must know that the first thing to do is to analyze the problem and see just what it requires. He must know that the abstraction depends upon the goal. The learner should be taught the sources of some of the commonest mistakes in judgment. For instance, if he knows of the tendency to respond in terms of analogy, and sees some of the errors to which accepting a minor likeness between two situations as identity lead, he will be much more apt to avoid such mistakes than would otherwise be true. If he knows how unsafe it is to form a judgment on limited data,--if from his own and his classmates' thinking first, and later from the history of science, illustrations are drawn of the disastrous effect of such thinking, he will see the value of seeking sources of information and several points of view before forming his own judgment. In his study the child should be taught not to be satisfied until he has tested the correctness of his judgment by verifying the result. This is a very necessary part of studying. He should check up his own thinking by finding out through appeal to facts if it is so; by putting the judgment into execution; by consulting the opinion of others, and so on. Study may be considered from the point of view of the type of material which is used in the process. The student may be engaged on a problem which involves the use of apparatus or specimens of various kinds, or he may need to consult people, or he may have to use books. So far as the first type is concerned, it is obviously unwise to have a student at work on a problem which involves the use of material, unless the technique of method of use is well known. Until he can handle the material with some degree of facility it is waste of time for him to be struggling with problems which necessitate such use. Such practice results in divided attention, poor results from the study, and often bad habits in technique as well. Gaining the technique must be in itself a problem for separate study.