The Greek mind teaches the Arabs under the Caliphs of Bagdad and Cordova, and in turn the Arabian influence instructs the reviving European mind after the dark ages. The fall of Constantinople crushed the Greek mind completely. The genius and the "godlike men" of Rome vanished under the influence of the strong blood of the Goths, and the flourishing nations of the African shore have yielded so completely to physical and moral causes, that we justly doubt the story of their magnificence, their power, their intelligence. We see the effete races infused with the fresh blood; the vigorous juices of the Scandinavians march forward with unparalleled pace to the triumphs of reason and philosophy. The pure, warm, healthy vitality of the North recalls to life the exact sciences, the laws of reasoning, and philosophy, and æsthetics, which, arising from Grecian genius, had slumbered for a thousand years. XXIX. In the slave lands of America a high order of intellect was proclaimed; but when analysis approached, it sank into mediocrity, or vanished into dust, like the forms in the ancient tombs when exposed to the light of heaven. Slavery has produced nothing but horror. The flashes of light that have burst forth through its mists have been the expiring efforts of genius. Here the sciences have always languished and declined to take root, for they are the offspring of genius and reason. The arts never appeared, for the spirit of imitation never arose. To cultivate the sciences, there is need of exalted desire, which comes from healthy and prosperous races or from celestial fire. Here there was the barbarity of ignorance; the only desires were to increase the enormities of their crimes, by the spread and general adoption of Slavery, and to conceal its proportions and influences beneath a cloud of mental darkness, which is frightful to contemplate, when placed in comparison with intelligent communities like New England, Belgium, and Prussia. They thought to perpetuate an aristocratic power, and transmit the inheritance of Slavery as a blessing, but they forgot that in the formation of happy nations and states humanity forms the broad base; they forgot that ambitious and avaricious families quickly degenerate and disappear completely from the earth. The vicissitudes of political life hasten that decline which is commenced by riches and rank, when supported by morbid ideas and sentiments. The noble families of Athens and Corinth, the patrician body at Rome, vanished so rapidly as to excite the surprise of the nations they governed. The names of the descendants of the founders of Venice, written in the Libro di Oro, are no longer to be found among the living in Italy. The same law is silently at work in our times. XXX.