That men did not become aware of conscience as a peculiar power of the mind, till they had long reasoned and meditated upon actions and rules; --that they did not at first separate it from all other faculties, mark it by a name, and clearly discern its place;--may well be supposed. For with how much labour and doubt, and effort and struggle, have all abstract thoughts, however clear, all foundations of general truths, however sure, been extricated by man from the complex mass of events and appearances which surround him. Tardily and gradually, no doubt, do the principles of moral truth emerge into view, even among the sagest and most virtuous of the heathen. But has not this been so with abstract truths of the plainest kinds? Even those portions of human knowledge to which we here turn men's eyes, as the very type and exemplar of evident and indisputable speculative truth;--the properties, I mean, of space and of number;--were not these, too, brought into view, late and slowly and partially, among the most acute and luminous intellects of the ancient world?--while, over the greater part of the earth, and during the greater portion of the earth's history, no clear apprehension at all of such doctrines has found place in men's minds. Yet who among us holds that therefore these doctrines are precarious? and who does not see that the faculties by which we apprehend the properties of space and number are not the less real, or the less trustworthy, because they require to be unfolded and expanded by exercise and by teaching.
William Whewell, On the Foundations of Morals, Sermon II.