"For the value of these teachings will perhaps be most fully realized when we clearly perceive that they are scientific in their character rather than controversial... Spiritual truths, if they are truths, may evidently be dealt with in a no less scientific spirit than chemical reactions. And no religious feeling, of whatever colour it may be, need be disturbed by the importation into the general stock of knowledge of new discoveries about the constitution and nature of man on the plane of his higher activities."