Thus it is that an intellectual synthesis, or systematic study of the laws of nature, is needed on far higher grounds than those of satisfying our theoretical faculties, which are, for the most part, very feeble, even in men who devote themselves to a life of thought. It is needed, because it solves at once the most difficult problem of the moral synthesis. The higher impulses within us are brought under the influence of a powerful stimulus from without. By its means they are enabled to control our discordant impulses, and to maintain a state of harmony towards which they have always tended, but which, without such aid, could never be realized. Moreover, this conception of the order of nature evidently supplies the basis for a synthesis of human action; for the efficacy of our action depends entirely upon their conformity to this order. But this part of the subject has been fully explained in my previous work, and I need not enlarge upon it further. As soon as the synthesis of mental conceptions enables us to form a synthesis of feelings, it is clear that there will be no very serious difficulties in constructing a synthesis of actions. Unity of action depends upon unity of impulse, and unity of design; and thus we find that the co-ordination of human nature, as a whole, depends ultimately upon the co-ordination of mental conceptions, a subject which seemed at first of comparatively slight importance. The subjective principle of Positivism, that is, the subordination of the intellect to the heart is thus fortified by an objective basis, the immutable Necessity of the external world; and by this means it becomes possible to bring human life within the influence of social sympathy. The superiority of the new synthesis to the old is even more evident under this second aspect than under the first. In theological systems the objective basis was supplied by spontaneous belief in a supernatural Will. Now, whatever the degree of reality attributed to these fictions, they all proceeded from a subjective source; and therefore their influence in most cases must have been very confused and fluctuating. In respect of moral discipline they cannot be compared either for precision, for force, or for stability, to the conception of an invariable Order, actually existing without us, and attested, whether we will or no, by every act of our existence. [Our conception of this External Order has been gradually growing from the earliest times, and is but just complete]