The nearest approach to a satisfactory substitute for the term “mystic sense” in terms of the reason is “conceptual reason.” It furnishes us with the thought of a faculty which has procreative or generative properties capable of being fertilized by intercourse with that which is separate from and higher than itself. Its first activity is to lay itself over against that which, though partaking of its own nature, is not itself. It is not self-fertilizing and can conceive or beget only after having perceived and apprehended.[1] It has constant regard for an objective and communication with it. The operation of the Mystic Sense is summed up in the single word faith, which is described as the giving substance to that which is hoped for, the testing of things not seen.[2] There is no objection to letting the world faith cover the whole working of the Mystic Sense, provided it is not restricted to a severely religious meaning. It is thus that it is commonly understood, or at any rate when applied in other connections it is assumed to be the working of a different faculty from that exercised in the sphere of religion. In its distinctively religious meaning, faith is the operation of the Mystic Sense in its highest employment. There is no one faculty that is reserved exclusively for religious employment. The fact is that religious faith is no more separate from the processes of the Mystic Sense which appropriate health for the body, hypotheses for the mind, working principles for the man of action, and ideals for the character, or independent of them, than the act of physical perception, which enables us to touch the stars, is separate from that use of the sensory nerves which relates us to the book we handle, or independent of it. They are both the result of a single faculty, or group of faculties, operating in different altitudes. Faith will be accepted in these pages as a philosophic term. Thus we speak of scientific faith, moral faith, and religious faith with equal appropriateness, meaning the Mystic Sense operating respectively in the interests of the scientific, of the moral, and of the religious.