I am merely attempting to set forth the general fact that as a social development goes on, inequality tends to establish itself, and not to point out the particular sequence, which must necessarily vary with different conditions. But this main fact makes intelligible all the phenomena of petrifaction and retrogression. The unequal distribution of the power and wealth gained by the integration of men in society tends to check, and finally to counterbalance, the force by which improvements are made and society advances. On the one side, the masses of the community are compelled to expend their mental powers in merely maintaining existence. On the other side, mental power is expended in keeping up and intensifying the system of inequality, in ostentation, luxury, and warfare. A community divided into a class that rules and a class that is ruled--into the very rich and the very poor--may "build like giants and finish like jewelers;" but it will be monuments of ruthless pride and barren vanity, or of a religion turned from its office of elevating man into an instrument for keeping him down. Invention may for a while to some degree go on; but it will be the invention of refinements in luxury, not the inventions that relieve toil and increase power. In the arcana of temples or in the chambers of court physicians knowledge may still be sought; but it will be hidden as a secret thing, or if it dares come out to elevate common thought or brighten common life, it will be trodden down as a dangerous innovator. For as it tends to lessen the mental power devoted to improvement, so does inequality tend to render men adverse to improvement. How strong is the disposition to adhere to old methods among the classes who are kept in ignorance by being compelled to toil for a mere existence, is too well known to require illustration, and on the other hand the conservatism of the classes to whom the existing social adjustment gives special advantages is equally apparent. This tendency to resist innovation, even though it be improvement, is observable in every special organization--in religion, in law, in medicine, in science, in trade guilds; and it becomes intense just as the organization is close. A close corporation has always an instinctive dislike of innovation and innovators, which is but the expression of an instinctive fear that change may tend to throw down the barriers which hedge it in from the common herd, and so rob it of importance and power; and it is always disposed to guard carefully its special knowledge or skill. It is in this way that petrifaction succeeds progress. The advance of inequality necessarily brings improvement to a halt, and as it still persists or provokes unavailing reactions, draws even upon the mental power necessary for maintenance, and retrogression begins. These principles make intelligible the history of civilization.