On the other hand, the difference between rich and poor was much less marked in the ancient world than it is in the modern. This is, perhaps, the most striking and important of the lines of cleavage between the world of antiquity and that of to-day. The idea of the moral equality of men, who are all sons of God, which was disseminated by Christianity; the idea of political and social equality, which was promulgated by the French Revolution, have in modern civilisation cut at the roots of the ancient distinctions of class, of religion, and even to a certain extent of nationality. But modern society is organising itself, in compensation, into a hierarchy of wealth. Men may consider themselves in theory all equal to one another; but each tries to associate with those persons who have approximately the same means as he, because it is they who are able to have the same habits as he has. Precisely because the modern world is so rich and so luxurious, the modes of living among the richest, the rich, and the moderately well-to-do classes show striking differences. And what is true of the modes of living is also true of tastes and inclinations. Everybody realises nowadays that differences or resemblances in habits, tastes, and inclinations are what most attract and repel men and influence them in treating each other as equals or unequals, when custom and tradition have established no other moral difference between them. The motor-car is as powerful a barrier between the social classes of to-day as was aristocratic prejudice before the Revolution. In ancient times, on the other hand, precisely because the world was then so much poorer and simpler, the difference in the mode of living between poor and rich was much smaller. Both lived in closer contact, treating each other really as equals, provided always that they were of the same rank socially and politically. Augustus, who could not have freedmen, however enlightened, to dinner, invited poor, but free-born, plebeians. A rich Roman would never have entertained a freedman in his house or at his table, or treated him as an equal, even if the latter had been as rich as, or richer than, himself. On the other hand, he welcomed and treated as an equal a citizen free-born like himself, however miserable and reduced to living on his bounty.