It should be known that at the beginning of a dynasty, taxation yields a large revenue from small assessments. At the end of the dynasty, taxation yi… - Ibn Khaldun

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

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.