In short, classic thought accepted a feudally arranged order of classes or kinds, each "holding" from a superior and in turn giving the rule of conduct and service to an inferior. This trait reflects and parallels most closely the social situation we were considering at the last hour. We have a fairly definite notion of society as organized upon the feudal basis. The family principle, the principle of kinship is strong, and especially is this true as we ascend in the social scale. At the lower end, individuals may be lost more or less in the mass. Since all are parts of the common herd, there is nothing especial to distinguish their birth. But among the privileged and ruling class the case is quite different. The tie of kinship at once marks a group off externally and gives it distinction, and internally holds all its members together. Kinship, kind, class, genus are synonymous terms, starting from social and concrete facts and going to the technical and abstract. For kinship is a sign of a common nature, of something universal and permanent running through all particular individuals, and giving them a real and objective unity. Because such and such persons are kin they are _really_, and not merely conventionally, marked off into a class having something unique about it. All contemporary members are bound into an objective unity which includes ancestors and descendants and excludes all who belong to another kin or kind. Assuredly this parcelling out of the world into separate kinds, each having its qualitatively distinct nature in contrast with other species, binding numerically distinct individuals together, and preventing their diversities from exceeding fixed bounds, may without exaggeration be called a projection of the family principle into the world at large. In a feudally organized society, moreover, each kinship group or species occupies a definite place. It is marked by the possession of a specific _rank_ higher or lower with respect to other grades. This position confers upon it certain privileges, enabling it to enforce certain claims upon those lower in the scale and entailing upon it certain services and homage to be rendered to superiors. The relationship of causation, so to speak, is up and down. Influence, power, proceeds from above to below; the activities of the inferior are performed with respect, quite literally, to what is above. Action and reaction are far from being equal and in opposite directions. All action is of one sort, of the nature of lordship, and proceeds from the higher to the lower. Reaction is of the nature of subjection and deference and proceeds from lower to higher. The classic theory of the constitution of the world corresponds point by point to this ordering of classes in a scale of dignity and power.