The Thought Experimental Method: Avicenna's Flying Man Argument

No argument from the Arabic philosophical tradition has received more scholarly attention than Avicenna's 'flying man' thought experiment, in which a human is created out of thin air and is able to grasp his existence without grasping that he has a body. This paper offers a new interpretation of the version of this thought experiment found at the end of the first chapter of Avicenna's treatment of soul in the Healing. We argue that it needs to be understood in light of an epistemological theory set out elsewhere by Avicenna, which allows that all the constitutive properties of an essence will be clear to someone who understands and considers that essence. On our reading, this theory is put to work in the 'flying man': because the flying man would grasp that his own essence has existence without grasping that he has a body, connection to body cannot be constitutive of the essence

Meaning and definition:Skepticism and semantics in twelfth-century Arabic Philosophy

The theory of essential definitions is a fundamental anti-sceptic element of the Aristotelian-Avicennian epistemology. In this theory, when we distinguish the genus and the specific differentia of a given essence we thereby acquire a scientific understanding of it. The aim of this article is to analyse systematically the sceptical reasons, arguments and conclusions against real definitions of three major authorities of twelfth-century Arabic philosophy: Fahr al-Din al-Razi, Sihab al-Din al-Suhrawardi and Abu l-Barakat al-Badadi. I focus on showing how their refutation of our capacity to provide essential definitions of things is rooted in their semantic theory: we only know things under certain descriptions which are identical to the meanings of the words that we use to refer to them, yet these descriptions do not capture the essences of things in themselves. The best result one can achieve with Aristotelian-Avicennian scientific definitions is a "nominal definition". With this, Razi, Suhrawardi and Abu l-Barakat will put some serious epistemic limitations on our capacity to attain scientific knowledge of things, at least as Aristotle and Avicenna would have it