Some years ago I had a need for an attorney to perform for me a petty service. Just at that critical moment I met a friend who was a lawyer. I employed him forthwith. At a later time I needed a lawyer again, recalled my <p 294> former experience, and called up the same attorney. This employing him the second time was clearly a practical judgment. If I have frequent need for an attorney, I shall probably make use of my preformed practical judgment and employ this same attorney. This act will never become a habit, but it will approximate more and more a habitual action, and will seem to be performed intuitively, and will be an illustration of an expert judgment. This morning I was asked to find a cook and man of general utility for an outing camp. I had no preformed practical judgment which I could apply to the case and did not even possess a remembrance of any experience upon which I might base a practical experience. In such a case therefore I am not only not an expert but I do not possess the necessary preliminary experiences for developing such ability. During the last decade I have given much thought to this question: Does the efficiency of one's thinking depend at all upon the clearness and distinctness of the mental image used <p 295> in the thinking? I settled the question in the negative. The formation of this principle (clear thinking does not depend upon clear visual image) was an act of reflective judgment. But now the application of this preformed judgment has developed into an expert judgment. Recently I was given the manuscript of a course in psychology and asked to appraise it. One of the chief points of the author was to advise all business men to develop clear visual images. In fact he asserted that clearness of thinking was in proportion to clearness of the visual image with which the thinking is carried on. Without again weighing the evidence for my principle, I applied my preformed judgment and by means of this expert judgment condemned the course. A man is expert only in those fields in which he has developed the appropriate habits, the necessary, practical, and reflective judgments, and has had some practice in applying these judgments. We find that four classes of experiences are valuable, _i.e_. such experiences as result in the <p 296> formation of habits; such as result in practical judgments, in reflective judgments, and in expert judgments. Our final task is to consider methods for increasing the probabilities that such experiences may be secured and utilized. SECURING AND UTILIZING THESE MOST VALUABLE EXPERIENCES The conditions best adapted for procuring and utilizing one class of these most valuable experiences may not be the best for the other three classes. Our final problem must therefore be subdivided into four parts corresponding to the four classes of valuable experience. _Special Conditions Favorable to Habit Formation_