The story of the flying man

This story is found in Ibn Sina's work The Healing (al-Shifa'), which is a philosophical and scientific encyclopedia that covers logic, physics, mathematics, metaphysics, psychology, and theology. The story is part of Ibn Sina's argument for the immateriality and individuality of the human soul.

The story asks the reader to imagine a man who is suspended in the air, isolated from all sensations of touch and sight. He does not feel his own body or see anything around him. He does not remember anything from his past or anticipate anything in his future. He only has a consciousness of his own existence.

Ibn Sina then asks: Does this man affirm the existence of his self? He answers: Yes, he does. He knows that he exists, even though he does not know anything else. He does not need any bodily organ or external object to know his own existence.

Ibn Sina then concludes: This shows that the self is not identical with the body or any of its parts. It is a simple and indivisible substance that is distinct from matter. It is also unique and incommunicable, since no one else can share in its existence or know it as it knows itself.

This story shows Ibn Sina's view of human nature as having a rational soul that transcends the physical world and can attain knowledge of itself and God. 

It also shows his critique of the materialist and empiricist views that deny the reality of the soul and its immortality. It is considered to be one of the earliest examples of thought experiments in philosophy.