Simia quam similis, turpissima bestia, nobis?--ENNIUS. Tous les homines se ressemblent si fort qu'il n'y a point de peuple dont les sottises ne nous doivent faire trembler.--FONTENELLE. The savage is very close to us indeed, both in his physical and mental make-up and in the forms of his social life. Tribal society is virtually delayed civilization, and the savages are a sort of contemporaneous ancestry.--WILLIAM I. THOMAS. 6. OUR ANIMAL HERITAGE. THE NATURE OF CIVILIZATION There are four historical layers underlying the minds of civilized men--the animal mind, the child mind, the savage mind, and the traditional civilized mind. We are all animals and never can cease to be; we were all children at our most impressionable age and can never get over the effects of that; our human ancestors have lived in savagery during practically the whole existence of the race, say five hundred thousand or a million years, and the primitive human mind is ever with us; finally, we are all born into an elaborate civilization, the constant pressure of which we can by no means escape. Each of these underlying minds has its special sciences and appropriate literatures. The new discipline of animal or comparative psychology deals with the first; genetic and analytical psychology with the second;[10] anthropology, ethnology, and comparative religion with the third; and the history of philosophy, science, theology, and literature with the fourth. We may grow beyond these underlying minds and in the light of new knowledge we may criticize their findings and even persuade ourselves that we have successfully transcended them. But if we are fair with ourselves we shall find that their hold on us is really inexorable. We can only transcend them artificially and precariously and in certain highly favorable conditions. Depression, anger, fear, or ordinary irritation will speedily prove the insecurity of any structure that we manage to rear on our fourfold foundation. Such fundamental and vital preoccupations as religion, love, war, and the chase stir impulses that lie far back in human history and which effectually repudiate the cavilings of ratiocination. In all our reveries and speculations, even the most exacting, sophisticated, and disillusioned, we have three unsympathetic companions sticking closer than a brother and looking on with jealous impatience--our wild apish progenitor, a playful or peevish baby, and a savage. We may at any moment find ourselves overtaken with a warm sense of camaraderie for any or all of these ancient pals of ours, and experience infinite relief in once more disporting ourselves with them as of yore. Some of us have in addition a Greek philosopher or man of letters in us; some a neoplatonic mystic, some a mediaeval monk, all of whom have learned to make terms with their older playfellows.