Social consolidation is, however, not a simple problem, for social consolidation implies an equivalent capacity for administration. I take it to be an axiom, that perfection in administration must be commensurate to the bulk and momentum of the mass to be administered, otherwise the centrifugal will overcome the centripetal force, and the mass will disintegrate. In other words, civilization would dissolve. It is in dealing with administration, as I apprehend, that civilizations have usually, though not always, broken down, for it has been on administrative difficulties that revolutions have for the most part supervened. Advances in administration seem to presuppose the evolution of new governing classes, since, apparently, no established type of mind can adapt itself to changes in environment, even in slow-moving civilizations, as fast as environments change. Thus a moment arrives when the minds of any given dominant type fail to meet the demands made upon them, and are superseded by a younger type, which in turn is set aside by another still younger, until the limit of the administrative genius of that particular race has been reached. Then disintegration sets in, the social momentum is gradually relaxed, and society sinks back to a level at which it can cohere. To us, however, the most distressing aspect of the situation is, that the social acceleration is progressive in proportion to the activity of the scientific mind which makes mechanical discoveries, and it is, therefore, a triumphant science which produces those ever more rapidly recurring changes in environment to which men must adapt themselves at their peril. As, under the stimulant of modern science, the old types fail to sustain themselves, new types have to be equally rapidly evolved, and the rise of a new governing class is always synonymous with a social revolution and a redistribution of property. The Industrial Revolution began almost precisely a century and a half ago, since when the scientific mind has continually gained in power, and, during that period, on an average of once in two generations, the environment has so far shifted that a social revolution has occurred, accompanied by the advent of a new favored class, and a readjustment of wealth. I think that a glance at American history will show this estimate to be within the truth. At the same time such rapidity of intellectual mutation is without precedent, and I should suppose that the mental exhaustion incident thereto must be very considerable.