 al-Farabi |  Arabic and Islamic Philosophy, disciplines in: natural philosophy and natural science |  causation: medieval theories of |  Duns Scotus, John |  future contingents: medieval theories of |  Ibn Rushd [Averroes] |  Ibn Sina [Avicenna] |  Maimonides: the influence of Islamic thought on |  modality: medieval theories of |  Philoponus 