Ibn Kammuna, Sa‘d ibn Mansur

(d. 682/1284)

   Ibn Kammuna was a Jewish physician and philosopher whose thought was profoundly influenced by – and whose thought in turn profoundly influenced – the Islamic philosophical tradition. Some have even claimed that he converted to Islam, although there is some dispute about this. His central intellectual endeavor was to synthesize and clarify the two great philosophical systems of his time: the Peripatetic school and the Illuminationist school. His chief philosophical works include The New Philosophy (al-Jadid fi al-hikma), Commentary on [Ibn Sina’s] Remarks and Admonitions (Sharh al-Isharat wa al-tanbihat) and The Refinement and Commentary on [al-Suhrawardi’s] Intimations (al- Tanqihat fi sharh al-Talwihat). The last of these is generally considered one of the clearest and most exhaustive treatments of the philosophy of Illumination, and historically played a pivotal role in the formation of the ishraqi school. Ibn Kammuna is representative of the more discursive, systematic and scientific strain of the Illuminationist tradition. His powerfully analytic mind brought an unparalleled clarity and precision to the variety of topics he examined, whether he was refining and supplementing Aristotelian logic with his notions of conception and assent (ostensibly neglected processes of explanation and proof necessary to ground demonstrative science), refuting the mutakallimun’s ontology of atoms and accidents (by considering the nature of spatial extension and divisibility), clarifying debates concerning the createdness or eternity of the world (by distinguishing between ‘creation by essence’, which involves real ontological dependence, and ‘creation by time’, which simply involves temporal priority and in any case presupposes matter and motion), shedding new light on Ibn Sina’s distinction between essence and existence and al-Suhrawardi’s insistence on the primacy of essence (showing how ‘thingness’ [shay’iya] is more general than existence [wujud] and analyzing being into the three categories of being by itself and for itself, being for itself and not by itself, and being not for itself and not by itself), or demonstrating that the Necessary Existent must be unitary. He is particularly famous for his use of various paradoxes that later came to be known as Ibn Kammuna’s fallacies, and which earned him the title ‘the devil of the philosophers’. Among these are the possibility of two necessary existents, the existence of non-existent things, and the self-referential liar’s paradox, to which he proposed two possible solutions: rejecting the principle of bivalence and introducing a third truth value (neither true nor false) or classifying the sentence as false because the subject and object are not distinguished. He also composed a seminal work of comparative religion, Inquiries into Three Faiths (Tanqih al-abhath li al-milal al-thalath), which is still praised for its evenhanded, dispassionate and rigorous discussion of the creeds of the three monotheistic religions, focusing particularly on the phenomenon of prophecy. Unfortunately, the book was not well-received in its day. Its publication is said to have sparked a riot in Ibn Kammuna’s hometown of Baghdad in 682/1284, prompting the prince to order that the author be burned at the stake. Luckily, he escaped with the help of friends, fleeing to another city. He died later that year.

   See creation vs. eternity of the world; epistemology; essence and existence; Ibn Sina; Illuminationism; al-Suhrawardi

   Further reading: Ibn Kammuna 1971, 2002; Pourjavady and Schmidtke 2006