Is not the road-mender also a good Catholic, or in some other way, conventional or unconventional, religiously devout, piously doing, not his own, but another's work? Does not the scientist give point to the idea of another and different life, that is to say, of his life of knowledge not being the whole of life, by the agnosticism which he not only carefully asserts but also actually embodies as a factor in his method? The road-mender slaves at his humble task, ignorant and yet trustful, believing in an infallible wisdom and an absolute power, and the scientist lives with great enthusiasm to know the world as it is, but tells us at the same time with no less enthusiasm and with a meaning that certainly ought to temper his exclusiveness that the object which he studies and describes [p.064] is nevertheless really unknowable. To quote Mr. Spencer: "The man of science ... more than any other, truly _knows_ that in its ultimate essence nothing can be known." Surely there is meaning for Stevenson's story of Dr. Jekyll and Mr. Hyde in other fields besides that of morality. Class life must always involve its members in a protective or compensating duplicity. But now, whatever in the life of other classes this duplicity, which conserves the wholeness of life even when formally life is narrow and partial, ought to be called, in the profession of science it often goes under the name of dualism. Seen at different angles, it is now dualism, now objectivism, now agnosticism. In each of these different ways the scientist, quite outdoing or transcending his profession, recognizes a sphere of reality or a sphere of activity, that is beyond that of the knowledge which he makes his special business, and, as is very important to observe, the peculiar manner of his recognition of this sphere, or the peculiar character of his duplicity, is relative to just the abstraction which makes his science what it is. Thus his peculiar duplicity is one of conscious subject and unconscious, external object, of observing man and objective nature, of real knowledge and unknowable reality.