There have been many definitions of civilization. Civilization is a complexity of countless aspects, and may be validly defined in a great number of relationships. A reader of James Harvey Robinson's MIND IN THE MAKING will find it very reasonable to define a civilization as a system of society-making ideas at issue with reality. Just so far as the system of ideas meets the needs and conditions of survival or is able to adapt itself to the needs and conditions of survival of the society it dominates, so far will that society continue and prosper. We are beginning to realize that in the past and under different conditions from our own, societies have existed with systems of ideas and with methods of thought very widely contrasting with what we should consider right and sane to-day. The extraordinary neolithic civilizations of the American continent that flourished before the coming of the Europeans, seem to have got along with concepts that involved pedantries and cruelties and a kind of systematic unreason, which find their closest parallels to-day in the art and writings of certain types of lunatic. There are collections of drawings from English and American asylums extraordinarily parallel in their spirit and quality with the Maya inscriptions of Central America. Yet these neolithic American societies got along for hundreds and perhaps thousands of years, they respected seed-time and harvest, they bred and they maintained a grotesque and terrible order. And they produced quite beautiful works of art. Yet their surplus of population was disposed of by an organization of sacrificial slaughter unparalleled in the records of mankind. Many of the institutions that seemed most normal and respectable to them, filled the invading Europeans with perplexity and horror. When we realize clearly this possibility of civilizations being based on very different sets of moral ideas and upon different intellectual methods, we are better able to appreciate the profound significance of the schism in our modern community, which gives us side by side, honest and intelligent people who regard Birth Control as something essentially sweet, sane, clean, desirable and necessary, and others equally honest and with as good a claim to intelligence who regard it as not merely unreasonable and unwholesome, but as intolerable and abominable. We are living not in a simple and complete civilization, but in a conflict of at least two civilizations, based on entirely different fundamental ideas, pursuing different methods and with different aims and ends.