The animal energies themselves, in time, are affected by domestic conditions; and when Cæsar comes on the scene Rome is visibly far on the way to a state of things such as had long before appeared in older civilisations[53]--a state of things commonly but rather loosely called degenerate, in which the animal energies are grown less robust, and the life therefore in some respects more civilised. Such a course had been run in Italy long before the rise of Rome, notably in Etruria, where, after a conquest of aborigines by a small body of invaders,[54] who were in touch with early Greek culture, the civilisation remains at that archaic stage while Greek civilisation continues to progress.[55] There, with a small aristocracy lording it over a people of serfs,[56] progress of all kinds was arrested, and even the religion of the conquerors assimilated to that of the aborigines.[57] In the Rome of Cæsar we see, after much fluctuation, with a more complex and less enfeebled structure of population, the beginnings of the same fixation of classes; while, at the same time, there has been such psychological variation as can begin to give new and ostensibly higher channels to the immanent forces of union and strife. This is the social condition that, given the required military evolution, above all lends itself to imperialism or absolute monarchy; which system in turn best maintains itself by a policy of conquest, so employing the animal energies and keeping up the cohesive force of militarist pride throughout all classes. Even now, of course, in a semi-enslaved populace, as in a slave population pure and simple,[58] there were possibilities of insurrection; and it was at length empirically politic for the emperors to give the populace its daily bread and its daily games, as well as to keep it charmed with the spectacle of conquest. The expedient of doles of food did not at once condemn itself by dangerously multiplying mouths, because, although it was only in the upper classes that men commonly refused to marry and have legitimate children, population was now restrained by the preventive checks of vice, city life, and wholesale abortion,[59] which are so much more effective--alike against child and mother[60]--than the random resort to infanticide, though that too had greatly increased.[61]