tions, the compactness and size of its organization, and its importance in the mechanism of production increased or diminished.
In the course of the fluctuating struggles of these classes the older social forms, which had become untenable, were pushed aside for new ones. The social order which took the place of the old was not always immediately the best possible. In order to have made it so the revolutionary class of each epoch would have had to be in possession of the sole political power and the most perfect understanding of their social conditions. As long as this was not the case, mistakes were inevitable. Not infrequently a new social order proved itself partially, if not wholly, as untenable as the one overthrown. Nevertheless, the stronger the pressure of economic development, the clearer became its demands and the greater the ability of the revolutionary classes to do what was required of them. The institutions of the revolutionary class which were in opposition to the demands of economic development fell into decay and were soon forgotten. But those which had become necessary quickly struck root and could not be exterminated by the upholders of the former system.
It is in this way that all new social orders have arisen. Revolutionary periods differ from other periods of social development only by virtue of the fact that during them the phenomena of development proceed at an unusually rapid pace.
The genesis of a social institution is, it thus appears, very different from that of a building. Previously perfected plans are not applicable to
