Floating man experiential field shows that the self is not consequently a substance and thereby there is no subjectivity. On the other hand some scholars like Wisnovsky believe that the flying man argument proved the substantiality of the soul. Ibn Sina believes that innate awareness is completely independent of sensory experience. Before the French philosopher Descartes (1596–1650) pointed out the existence of the conscious self as a turning point in epistemology, using the phrase "Cogito ergo sum," the 11th century Iranian philosopher Avicenna had referred to the existence of consciousness in the flying man argument. Thus, long before Descartes, Avicenna had established
Cogito, ergo sum distinctiveness of self-evident propositions — to establish true and justified propositions despite having adopted a method of generalized doubt. As a consequence of this demonstration, Descartes considers science and mathematics to be justified to the extent that their proposals are established on a similarly immediate clarity, distinctiveness, and self-evidence that presents itself to the mind. The originality of Descartes's thinking, therefore, is not so much in expressing the "cogito" — a feat accomplished by other predecessors, as we shall see — but on using the "cogito" as demonstrating the most fundamental epistemological principle, that science and mathematics are justified by