By use this power develops, and it soon becomes as simple to alter a morbid taste which may have been a lifelong tendency as to alter the smallest of recently acquired bad habits. The following is an interesting experience with a pupil who was strongly inclined to a belief in the value and power of concentration. This pupil contested vigorously my attacks on the object of her faith, as practised in accordance with the orthodox conception. She put forward the usual arguments, of course, and I quite failed to make any impression on her mental attitude towards the vexed question under discussion. But at last, some days after our first encounter, my opportunity came. We were not at the time directly discussing concentration, but we were dealing with kindred subjects, and presently my pupil began to speak of the attitudes adopted by people towards the things in life that they like or dislike to do. Her own plan, she said, with a touch of pride, had been to develop the habit of keeping her mind on other and more pleasant subjects whenever she had been engaged in a task that was unsympathetic to her, and she had so far succeeded in the cultivation of this habit that the disagreeable sensations of any unpleasant duty were no longer experienced by her. I then put one or two questions to her and elucidated among other facts that for years she had been unable “to concentrate” when reading and that this difficulty was becoming constantly more pronounced. Fortunately this instance opened those locked places of her intelligence that I had been unable to reach by argument. I showed her how she had been cultivating a most harmful mental condition, which made concentration on those duties of life which pleased her appear as a necessity. She had been constructing a secret chamber in her mind, as harmful to her general well-being as an undiagnosed tumour might have been to her physical welfare. I am glad to say that she came to admit the truth of my original position and has since begun her efforts to carry out the suggestions I offered for the correction of her bad habit. And in all such efforts to apprehend and control mental habits, the first and only real difficulty is to overcome the preliminary inertia of mind in order to combat the subjective habit. The brain becomes used to thinking in a certain way, it works in a groove, and when set in action, slides along the familiar, well-worn path; but when once it is lifted out of the groove, it is astonishing how easily it may be directed. At first it will have a tendency to return to its old manner of working by means of one mechanical unintelligent operation, but the groove soon fills, and although thereafter we may be able to use the old path if we choose, we are no longer bound to it.