Editing Avicenna (section)

==== Psychology ====
Avicenna's legacy in classical psychology is primarily embodied in the ''Kitab al-nafs'' parts of his ''Kitab al-shifa'' (''The Book of Healing'') and ''Kitab al-najat'' (''The Book of Deliverance''). These were known in Latin under the title [[De Anima]] (treatises "on the soul").{{dubious|date=October 2012}} Notably, Avicenna develops what is called the [[Floating man|Flying Man]] argument in the Psychology of ''The Cure'' I.1.7 as defence of the argument that the soul is without quantitative extension, which has an affinity with [[Descartes]]'s ''cogito'' argument (or what [[phenomenology (philosophy)|phenomenology]] designates as a form of an "''epoche''").<ref name="Nader El-Bizri 2000 pp. 149-171">[[Nader El-Bizri]], ''The Phenomenological Quest between Avicenna and Heidegger'' (Binghamton, NY: Global Publications SUNY, 2000), pp.&nbsp;149–171.</ref><ref name="elbizri67-89">Nader El-Bizri, "Avicenna's De Anima between Aristotle and Husserl," in ''The Passions of the Soul in the Metamorphosis of Becoming'', ed. Anna-Teresa Tymieniecka (Dordrecht: Kluwer Academic Publishers, 2003), pp.&nbsp;67–89.</ref>

Avicenna's psychology requires that connection between the body and soul be strong enough to ensure the soul's individuation, but weak enough to allow for its immortality. Avicenna grounds his psychology on physiology, which means his account of the soul is one that deals almost entirely with the natural science of the body and its abilities of perception. Thus, the philosopher's connection between the soul and body is explained almost entirely by his understanding of perception; in this way, bodily perception interrelates with the immaterial human intellect. In sense perception, the perceiver senses the form of the object; first, by perceiving features of the object by our external senses. This sensory information is supplied to the internal senses, which merge all the pieces into a whole, unified conscious experience. This process of perception and abstraction is the nexus of the soul and body, for the material body may only perceive material objects, while the immaterial soul may only receive the immaterial, universal forms. The way the soul and body interact in the final abstraction of the universal from the concrete particular is the key to their relationship and interaction, which takes place in the physical body.<ref>{{Cite book |title=Avicenna's Psychology. An English translation of Kitāb al-Najāt, Book II, Chapter VI, with Historico-Philosophical Notes and Textual Improvements on the Cairo edition |last=Avicenna |publisher=Oxford University Press, Geoffrey Cumberlege |year=1952 |editor-last=F. Rahman |location=London |page=41}}</ref>

The soul completes the action of intellection by accepting forms that have been abstracted from matter. This process requires a concrete particular (material) to be abstracted into the universal intelligible (immaterial). The material and immaterial interact through the Active Intellect, which is a "divine light" containing the intelligible forms.<ref>{{Cite book |title=Avicenna's Psychology. An English translation of Kitāb al-Najāt, Book II, Chapter VI, with Historico-Philosophical Notes and Textual Improvements on the Cairo edition |last=Avicenna |publisher=Oxford University Press, Geoffrey Cumberlege |year=1952 |editor-last=F. Rahman |location=London |pages=68–69}}</ref> The Active Intellect reveals the universals concealed in material objects much like the sun makes colour available to our eyes.