The rise and growth of European civilization is too vast and complex a subject to be thrown into proper perspective and relation in a few paragraphs; but in all its details, as in its main features, it illustrates the truth that progress goes on just as society tends toward closer association and greater equality. Civilization is co-operation. Union and liberty are its factors. The great extension of association--not alone in the growth of larger and denser communities, but in the increase of commerce and the manifold exchanges which knit each community together and link them with other though widely separated communities; the growth of international and municipal law; the advances in security of property and of person, in individual liberty, and towards democratic government--advances, in short, towards the recognition of the equal rights to life, liberty, and the pursuit of happiness--it is these that make our modern civilization so much greater, so much higher, than any that has gone before. It is these that have set free the mental power which has rolled back the veil of ignorance which hid all but a small portion of the globe from men's knowledge; which has measured the orbits of the circling spheres and bids us see moving, pulsing life in a drop of water; which has opened to us the antechamber of nature's mysteries and read the secrets of a long-buried past; which has harnessed in our service physical forces beside which man's efforts are puny; and increased productive power by a thousand great inventions. In that spirit of fatalism to which I have alluded as pervading current literature, it is the fashion to speak even of war and slavery as means of human progress. But war, which is the opposite of association, can aid progress only when it prevents further war or breaks down antisocial barriers which are themselves passive war. As for slavery, I cannot see how it could ever have aided in establishing freedom, and freedom, the synonym of equality is, from the very rudest state in which man can be imagined, the stimulus and condition of progress. Auguste Comte's idea that the institution of slavery destroyed cannibalism is as fanciful as Elia's humorous notion of the way mankind acquired a taste for roast pig. It assumes that a propensity that has never been found developed in man save as the result of the most unnatural conditions--the direst want or the most brutalizing superstitions[46]--is an original impulse, and that he, even in his lowest state the highest of all animals, has natural appetites which the nobler brutes do not show. And so of the idea that slavery began civilization by giving slave owners leisure for improvement.