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 theHealing. 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. (shrink)