He who finds a new path is a pathfinder, even if the trail has to be found again by others; and he who walks far ahead of his contemporaries is a leader, even though centuries pass before he is recognized as such.
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 KhaldunTherefore, the Negro nation are, as a rule, submissive to slavery, because [Negroes] have little [that is essentially] human and have attributes that are quite similar to those of dumb animals, as we have stated.
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 Khaldun