The experiment
In the first chapter of the psychology (al-Nafs) of his encyclopaedia The Cure (al-Shifāʾ), Ibn Sīnā asks the reader to imagine being created instantaneously and perfect, sight veiled from external things, floating in air or a void so that not even the air’s resistance is felt, limbs held apart so they do not touch. Would such a person affirm the existence of his self? Ibn Sīnā says he would not hesitate — yet he would affirm no length, breadth or depth for it, no heart, no brain, no limb. Modern scholarship calls this the “flying” or “floating” man.
What it was meant to show
The background question in Aristotelian psychology was whether the soul is an enmattered form or a bodily capacity, or the body’s “perfection” (kamāl) that might be a separate substance. Ibn Sīnā prefers the latter and offers the experiment as pre-theoretical evidence available to anyone: what is affirmed (the self) differs from what is not affirmed (the body). Hence the human soul is distinct from the body — while plant and animal souls can remain forms in matter.
Self-awareness comes first
The Stanford Encyclopedia summarises it this way: a newly created person floating in a void, senses disabled, would still be self-aware, so the self one cognises cannot be a bodily thing known through the senses. Deborah Black shows that Ibn Sīnā went further in his late Investigations and Notes, compiled by students, reflecting at length on the soul’s awareness of itself, which he treats as always present even when we do not attend to it.
A common comparison
The Flying Man is often set beside Descartes’ “I think, therefore I am” six centuries later. The resemblance in form is real — both isolate the self from the body to test its certainty. The aims differ: Descartes seeks an indubitable foundation for all knowledge; Ibn Sīnā works inside Aristotelian psychology, asking what the soul is and how it relates to the body. Read each in its own context rather than claiming either borrowing or no connection. The De anima of the Shifāʾ was translated into Latin in the twelfth century and was widely read in medieval Europe.
Where the argument is weak
Critics, medieval and modern, object that imagining a self without a body does not prove it can exist without one: I may know a thing without knowing all its properties. Defenders reply that the argument rests not on imagination alone but on the difference between what awareness affirms directly and what it does not. That debate is why the thought experiment is still discussed in philosophy of mind.
Weekly exercise
Sit for two minutes with eyes closed and try to attend only to the fact that you exist, without thinking of your body or your surroundings. Did you really separate awareness from bodily feeling? Write two lines, then compare with Ibn Sīnā and his critics.
Further reading
Reference links for verification. This article is original Vemetto wording and does not copy source text.