^Ibn Khaldun, Muqaddimah, 2:272-73, quoted in Dieter Weiss (1995), "Ibn Khaldun on Economic Transformation", International Journal of Middle East Studies27 (1), p. 29-37 [30].
^Friedrich Hayek; "'Conscious Direction and the Growth of Reason" in The Counter-Revolution of Science: Studies on the Abuse of Reason (1980)