Realizing the importance of attention, the student will naturally wish to cultivate the power of bestowing it when necessary. The first role in the cultivation of the attention is that the student shall carefully acquire _the habit of thinking of or doing but one thing at a time_. This first rule may seem easy, but in practice it will be found very difficult of observance, so careless are the majority of us in our actions and thinking. Not only will the trouble and care bestowed upon the acquiring of this habit of thought and action be well repaid by the development of the attention, but the student will also acquire a facility for accomplishing his tasks quickly and thoroughly. As Kay says: "There is nothing that contributes more to success in any pursuit than that of having the attention concentrated on the matter in hand; and, on the contrary, nothing is more detrimental than when doing one thing to have the mind taken up with something else." And as Granville says: "A frequent cause of failure in the faculty of attention is striving to think of more than one thing at a time." Kay also well says: "If we would possess the power of attention in a high degree, we must cultivate the habit of attending to what is directly before the mind, to the exclusion of all else. All distracting thoughts and feelings that tend to withdraw the mind from what is immediately before it are therefore to be carefully avoided. This is a matter of great importance, and of no little difficulty. Frequently the mind, in place of being concentrated on what is immediately before it, is thinking of something else--something, it may be, that went before or that may come after, or something quite alien to the subject." The following principles of the application of the attention have been stated by the authorities: I. The attention attaches more readily to interesting than to uninteresting things. II. The attention will decline in strength unless there is a variation in the stimulus, either by a change of object or the developing of some new attribute in the object. III. The attention, when tired by continuous direction toward some unvarying object, may be revived by directing it toward some new object or in allowing it to be attracted and held by some passing object. IV. The attention manifests in a two-fold activity; _viz._ (1) the concentration upon some one object of thought; and (2) the shutting out of outside objects. Thus, it has its positive and negative sides. Thus, when a man wishes to give his undivided attention to one speaker in a crowd of speaking individuals, he acts positively in focusing his consciousness upon the selected individual, and negatively by refusing to listen to the others. V. The attention is not a faculty, but a means of using any faculty with an increased degree of efficiency.