Avicenna (980-1037 CE), whose full name was Abu Ali al-Husayn ibn Abd-Allah ibn Sina, was the most renowned, celebrated and influential philosopher of the golden age of Islamic learning, a towering figure to whom most later thinkers feel they had to respond to. He was a Persian, born near Bukhara, then the capital of the Persian Samanid dynasty. He was a philosopher of considerable self-confidence, great intellectual rigor and sophistication. In this succinct essay I will evaluate arguably the best known fictional thought experiment coming from the medieval Islamic World, proffered and developed by Avicenna, whilst imprisoned in the castle of Fardajan in the Persian province of Hamadan, the famous “ floating man”.
According to Avicenna, we cannot deny the consciousness of the self. To furnish his stance he used the floating man scenario.
The floating man is a sensory deprivation thought experiment – stunningly original- in which one should imagine as if one is created complete, fully developed and perfectly formed but in which one’s vision is veiled and shrouded from directly observing the things of the external world. One by divine intervention floats in midair, space or in a void, doesn’t perceive any perceptible current of the air that supports him, with limbs that are splayed out and kept out of contact with each other so that they cannot feel each other. Thus, he is in a state of total sensory deprivation. One further has no previous sensory experience, is devoid of any sensory input, sensations or sensible memories. Avicenna argues that even in such a deprived state the individual still would be self-aware or conscious of himself. He will have knowledge of his own essence or self and be aware of his own existence.
3. What is new under the sun?
Avicenna thus through the introspective thought experiment tries to demonstrate that the soul has reflexive knowledge of its own existence. He was intrigued by the fact that we are all always able to become aware of our own existence. What distinguishes us from the floating man is that our souls are awash with stimuli, memories and thoughts. We can make the mental faux pas by conflating self-awareness with having some sensory experience, some memory, some thought. However, Avicenna asserts that self-awareness is more fundamental than any such activity of the mind.
There are two central objections that have been raised against the floating man’s thought experiment. In primo there is the recent critique of Jari Kaukau who puts his worry as: Avicenna “seems to commit the rather blatant fallacy of proceeding from an epistemic or phenomenological distinction to a metaphysical one.” (Kaukau 2015:37). In other words in the floating man argument he senses the purported shift from a transparent to an opaque context. Some philosophers suggest though that this objection can be circumvented by lowering the bar on Avicenna’s behalf. I think though that the Kaukau’s argument is a killer whale argument since the proposed saving-face-and-grace circumvention doesn’t fit hand in glove with the text of Avicenna. It is more a classical case of damage control hineininterpretieren.
In secundo there is the objection that the thought experiment illicitly shifts from a hypothetical situation to a categorical conclusion. I personally don’t think this objection is as strong as the first one, since where we in our modern day parlance would speak of a “counterfactual thought experiment”, Avicenna would speak of something that has merely a mental existence. The objection can again be circumnavigated by reading the thought experiment differently.
What intrigues me most in Avicenna’s thought experiment is his insurmountable belief in the power of the mind to see what is essential and what is not essential. I think that if you take this belief as a leitmotiv, tweak his thought experiment while paralleling it with the sixth Meditation of Descartes you still can have an interesting field day with this thought experiment.
Can you prove the existence of a soul with the floating man? Some would say, the jury is still out, others would say we have a hung jury. I would say the jury is still floating.
Adamson, Peter. (2016) Philosophy in The Islamic World: A History of Philosophy without Any Gaps, Volume 3. Oxford: Oxford University Press.
Adamson, Peter and Benevich, Fedor (2018) The Thought Experimental Method: Avicenna’s Flying Man, Journal of the American Philosophical Association.
Kaukua, Jari. (2015) Self-Awareness in Islamic Philosophy: Avicenna and Beyond. Cambridge: Cambridge University Press.
Sorensen, Roy A. (1992) Thought Experiments, Oxford: Oxford University Press.