Ibn Khaldun

“The only people who accept slavery are the Negroes, owing to their low degree of humanity and proximity to the animal stage. Other persons who accept the status of slave do so as a means of attaining high rank, or power, or wealth, as is the case with the Mameluke Turks in the East and with those Franks and Galicians who enter the service of the state [in Spain].”

“The sciences of only one nation, the Greeks, have come down to us, because they were translated through Al-Ma'mun's efforts. He was successful in this direction because he had many translators at his disposal and spent much money in this connection.”

“Eventually, Aristotle appeared among the Greeks. He improved the methods of logic and systematized its problems and details. He assigned to logic its proper place as the first philosophical discipline and the introduction to philosophy. Therefore he is called the First Teacher.”

“Businesses owned by responsible and organized merchants shall eventually surpass those owned by wealthy rulers.”

“Royal authority is a noble and enjoyable position. It comprises all the good things of the world, the pleasures of the body, and the joys of the soul. Therefore, there is, as a rule, great competition for it. It rarely is handed over (voluntarily), but it may be taken away. Thus, discord ensues. It leads to war and fighting, and to attempts to gain superiority.”

“All the sciences came to exist in Arabic. The systematic works on them were written in Arabic writing.”