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 and the History of Madness at the end of the renaissance and the beginning of the classical age. He then discusses the treatment of madness by Descartes in the "Meditations on First Philosophy". Foucault argues that Descartes refuses to recognise a commonality between himself and people who are mad and uses this dissociation as an excuse not to take madness seriously as a grounds for doubt. For Foucault this exclusion of madness by Descartes leads to a cogito that is more or less arbitrarily self-assured of its own rationality. Derrida argues that Descartes might appear to dismiss madness at the point of the meditation to