So far I have exemplified what seems to me real or genuine aims and applications of metaphysical study. I now proceed to the objects that are more or less factitious. We are here on delicate ground, and run the risk of discrediting our pursuit, as regards the very things that in the eyes of many people make its value. First, then, as psychology involves all our sensibilities, pleasures, affections, aspirations, capacities, it is thought on that ground to have a special nobility and greatness, and a special power of evoking in the student the feelings themselves. The mathematician, dealing with conic sections, spirals, and differential equations, is in danger of being ultimately resolved into a function or a co-efficient; the metaphysician, by investigating conscience, must become conscientious; driving fat oxen is the way to grow fat. [MAN'S RELATIONS TO THE INFINITE.] But to pass to a far graver application. It has usually been supposed that metaphysical theory is more especially akin to the speculation that mounts to the supernatural and the transcendental world. "Man's relations to the infinite" is a frequent phrase in the mouth of the metaphysician. Metaphysics is supposed to be "philosophy" by way of eminence; and philosophy in the large sense has not merely to satisfy the curiosity of the human mind, it has to provide scope for its emotions and aspirations; in fact, to play the part of theology. In times when the prevailing orthodox beliefs are shaken, some scheme of philosophy is brought forward to take their place. If I understand aright the drift of the German metaphysical systems for a century back, they all more or less propose to themselves to supply the same spiritual wants as religion supplies. In our own country, such of us as are not under German influence put the matter differently; but we still consider that we have something to say on the "highest questions". We are apt to believe that on us more than on any other class of thinkers, does it depend whether the prevailing theology shall be upheld, impugned, or transformed. The chief weapons of the defenders of the faith are forged in the schools of metaphysics. Locke and Butler, Reid, Stewart and Brown are theological authorities. And when theology is attacked, its metaphysical buttresses have to be assailed as the very first thing. If these are declared unsound, either it must fall, or it must change its front. It is Natural Theology, more particularly, that is thus allied to metaphysics; yet, not exclusively; for the defence of Revelation by miracles involves at the outset a point of logic.