To the formula of Jesus, "Thou shalt love thy neighbor as thyself," the answer is obvious enough: "Suppose my neighbor is not worthy of as much love as myself?" To be sure, it is a perilous thing for me to have to decide this question; nevertheless, it may be a fact that I am a great inventor, and that my neighbor is a sexual pervert. There is, of course, a sense in which I may love him, even so; I may love the deeper possibilities of his nature, which religious ecstasy can appeal to and arouse. But in spite of all ecstasies and all efforts, it may be that his disease--physical, mental and moral--has progressed to such a point that it is necessary to confine him, or to castrate him, or even to asphyxiate him painlessly. To say that I must love such a man as myself is, to say the least, to be vague. We can see how the indiscriminate preaching of such a formula would open the flood-gates of sentimentality and fraud. Modern thinking says: Thou shalt love the highest possibilities of life, and thou shalt labor diligently to foster them; moreover, because life is always growing, and new possibilities are forever dawning in the human spirit, thou shalt keep an open mind and an inquiring temper, and be ready at any time to begin life afresh. Such is the formula. It is not simple; and when we come to apply it, we find that it constantly grows more complex. When we attempt to decide our duty to ourselves, we find that we have in us a number of different beings, each with separate and sometimes conflicting duties and needs. We have in us the physical man and the economic man, and these clamor for their rights, and must have at least a part of their rights, before we can go on to be the intellectual man, the moral man, or the artistic man. So our life becomes a series of compromises and adjustments between a thousand conflicting desires and duties; between the different beings which we might be, but can be only to a certain extent, and at certain times. We shall see, as we come to investigate one field after another of human activity, that we never have an absolute certainty, never an absolute right, never an absolute duty; never can we shut our eyes, and go blindly ahead upon one course of action, to the exclusion of every other consideration! On the contrary, we sit in the seat of self-determination as a highly trained and skillful engineer. We keep our eyes upon a dozen different gauges; we press a lever here and touch a regulator there; we decide that now is a time for speed, and now for caution; and knowing all the time that the safety, not merely of ourselves, but of many passengers, depends upon the decisions of each moment. CHAPTER XI THE MIND AND THE BODY (Discusses the interaction between physical and mental things, and the possibility of freedom in a world of fixed causes.)