The history of religion is the history of man's search for God. That search depends for its success, in part, upon man's will. Christianity cannot be stationary: the extent to which we push our missionary outposts forward gives us the measure of our vitality. And in that respect, as in others, the vitality of the United States is great . . . 239-265 APPENDIX . . . . . . . . . . . . . . . . . . . . . . 266 _ad fin._ {1} INTRODUCTION Of the many things that fill a visitor from the old country with admiration, on his first visit to the United States, that which arrests his attention most frequently, is the extent and success with which science is applied to practical purposes. And it is beginning to dawn upon me that in the United States it is not only pure science which is thus practically applied,--the pure sciences of mechanics, physics, mathematics,--but that the historic sciences also are expected to justify themselves by their practical application; and that amongst the historic sciences not even the science of religion is exempted from the common lot. It also may be useful; and had better be so,--if any one is to have any use for it. It must make itself useful to the man who has practical need of its results and wishes to apply them--the missionary. He it is who, for the practical purposes of the work to which he is called, requires an applied science of religion; and Hartford {2} Theological Seminary may, I believe, justly claim to be the first institution in the world which has deliberately and consciously set to work to create by the courses of lectures, of which this series is the very humble beginning, an applied science of religion. How, then, will the applied science differ from the pure science of religion? In one way it will not differ: an applied science does not sit in judgment upon the pure science on which it is based; it accepts the truths which the pure science presents to all the world, and bases itself upon them. The business of pure science is to discover facts; that of the applied science is to use them. The business of the science of religion is to discover all the facts necessary if we are to understand the growth and history of religion. The business of the applied science is, in our case, to use the discovered facts as a means of showing that Christianity is the highest manifestation of the religious spirit.