When incentive to acquire and obtain property is gone, people no longer make efforts to acquire any... Those who infringe upon property rights commit an injustice... If this occurs repeatedly, all incentives to cultural enterprise are destroyed and they cease utterly to make an effort. This leads to destruction and ruin of civilization.
Ibn KhaldunIf the soul is impartial in receiving information, it devotes to that information the share of critical investigation the information deserves, and its truth or untruth thus becomes clear. However, if the soul is infected with partisanship for a particular opinion or sect, it accepts without a moment's hesitation the information that is agreeable to it. Prejudice and partisanship obscure the critical faculty and preclude critical investigation. The results is that falsehoods are accepted and transmitted.
Ibn KhaldunThe 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.
Ibn KhaldunEventually, 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.
Ibn Khaldun