Judging by my friend's letters, of which the last I have is written fourteen months after the Yoga training began, there can be no doubt of his relative regeneration. He has undergone material trials with indifference, travelled third-class on Mediterranean steamers, and fourth-class on African trains, living with the poorest Arabs and sharing their unaccustomed food, all with equanimity. His devotion to certain interests has been put to heavy strain, and nothing is more remarkable to me than the changed moral tone with which he reports the situation. A profound modification has unquestionably occurred in the running of his mental machinery. The gearing has changed, and his will is available otherwise than it was. My friend is a man of very peculiar temperament. Few of us would have had the will to start upon the Yoga training, which, once started, seemed to conjure the further willpower needed out of itself. And not all of those who could launch themselves would have reached the same results. The Hindus themselves admit that in some men the results may come without call or bell. My friend writes to me: "You are quite right in thinking that religious crises, love-crises, indignation-crises may awaken in a very short time powers similar to those reached by years of patient Yoga-practice." Probably most medical men would treat this individual's case as one of what it is fashionable now to call by the name of "self-suggestion," or "expectant attention"--as if those phrases were explanatory, or meant more than the fact that certain men can be influenced, while others cannot be influenced, by certain sorts of _ideas_. This leads me to say a word about ideas considered as dynamogenic agents, or stimuli for unlocking what would otherwise be unused reservoirs of individual power. One thing that ideas do is to contradict other ideas and keep us from believing them. An idea that thus negates a first idea may itself in turn be negated by a third idea, and the first idea may thus regain its natural influence over our belief and determine our behavior. Our philosophic and religious development proceeds thus by credulities, negations, and the negating of negations. But whether for arousing or for stopping belief, ideas may fail to be efficacious, just as a wire, at one time alive with electricity, may at another time be dead. Here our insight into causes fails us, and we can only note results in general terms. In general, whether a given idea shall be a live idea depends more on the person into whose mind it is injected than on the idea itself. Which is the suggestive idea for this person, and which for that one? Mr. Fletcher's disciples regenerate themselves by the idea (and the fact) that they are chewing, and re-chewing, and super-chewing their food. Dr. Dewey's pupils regenerate themselves by going without their breakfast--a fact, but also an ascetic idea. Not every one can use _these_ ideas with the same success.