2. WHAT CONSTITUTES SUBSTANTIAL AGREEMENT?--To be sure, we may be very generous in our interpretation of what constitutes substantial agreement; we may deny significance to all sorts of discrepancies by relegating them to the unimpressive class of "disputes about particulars." Such an impressionistic indifference to detail may leave us with something on our hands as little serviceable as a composite photograph made from individual objects which have little in common, a blur lacking all definite outline and not recognizable as any object at all. No man can guide his conduct by the common core of many or of all moral codes. Taken in its bald abstraction, it is not a code or anything like a code. Who can walk, without walking in some particular way, in some direction, at some time? Who can mind his manners without being mannerly in accordance with the usages of some race or people? Those who content themselves with enunciating very general moral principles may, it is true, be of no little service to their fellow-men; but that is only because their fellow-men are able to supply the details that convert the blur into a picture. Some twenty-four hundred years ago Heraclitus told his contemporaries "to act according to nature with understanding"; we are often told today that the rule of our lives should be "to do good." Had the ancient Greek not possessed his own notions of what might properly be meant by nature and by understanding, did we not ourselves have some rather definite conception of what actions may properly fall under the caption of doing good, such admonitions could not lead to the stirring of a finger. Who would appeal to his physician for advice as to diet, if he expected from him no more than the counsel to eat, at the proper hours, enough, but not too much, of suitable food? If, then, we confine our admonitions to the group of abstractions which constitute the universally acknowledged standard of virtue when all the individual differences which characterize different codes have been ignored, we preach what, taken alone, no man can live by, and no community of men has ever attempted to live by. If we leave it to our hearers to drape our naked abstractions with concrete details, each will set to work in a different way. The method of the composite photograph seems unprofitable in attempting to solve the problem of morals. 3. DOGMATIC ASSUMPTION.--There is, however, a second way by which the variations which characterize different codes may come to be relegated to a position of relative insignificance. We may assume that our own code is the ultimate standard by which all others are to be judged, and we may set down deviations from it to the account of the ignorance or the perversity of our fellowmen. So regarded, they are aberrations from the normal, and only true code of conduct; interesting, perhaps, but little enlightening, for they can have little bearing upon our conception of what we ought to do.