This would above all be the case if, reasoning by analogy, we provisionally accept, as the probable nearest approach to man’s direct ancestors, the actual Anthropoids. These, such as the Gorilla, are undoubtedly amongst the most unsocial of animals as regards the attitude of the adult males _inter se_. From the very difficulty of the problem of the congregation of such creatures in friendly unison within the group, we may infer that, in its solution, there will be found the key to the whole question of the Ascent from Brute to Man. In that ascent, Habit, the parent of Law, must have been conquered, and modified into the direction of novel Custom, a shock to the older economy of life. Again, the new rule of conduct, necessarily inchoate (considering the presumed feeble intellectuality of the creatures concerned, animals more or less brutish) must yet be of facile interpretation to its subjects, though, as befits _Homo alalus_, it must have been quite mute in operation. The new Rule of Conduct would not be expressed in terms of speech, a function, _ex hypothesi_ not yet evolved. The rule, as it was to my mind, I here propose to attempt to unfold as the ‘Primal Law;’ hoping to show that therein lay the beginning of law and order, and that, whilst itself arising in a natural manner, in its incidental creation of a first standard of a possible right and wrong, it laid, so to speak, one of the foundations of that moral sense, which has seemed to place so wide a space between man and other creatures. The prior existence of this law, in the semi-brutish stage of our physical and ethical evolution, might have been deductively evolved, even if no traces of it had remained to our day. It will be, however, my endeavour to point out that evidence of its existence (abundant as it appears to me) is to be found in certain obscure customs which are common to most actual savage races. The customs of so-called ‘avoidance’ between near relations will have the principal interest for us, although primitive marriage and inheritance will be found of corroborative value. Survivals and myths can be shown to point to the undeniable occurrence of this ‘Primal Law’ in the earlier life-history of the non-civilised peoples. The myths, however, may be merely early guesses about the unknown past of the race.