“One of us must imagine himself so as to be created all at once and perfect, but with his sight veiled so that he cannot see anything external, and floating in the air, so that he feels nothing. Would he affirm the existence of his self? He would not doubt the affirmation of his self.”

What does it mean?

Even stripped of every sensation, Ibn Sina argues, a person would still affirm that he or she exists, so the self affirmed is not identical with the body that is sensed. The usual reading takes the floating man as a thought experiment about self-awareness without sensory content, while a rival reading thinks the scene smuggles in the awareness it claims to isolate and so cannot prove a soul distinct from the body. The passage sits in the psychology of the Book of Healing, and the English here condenses a longer Arabic argument rather than quoting one canonical sentence.

Did Ibn Sīnā (Avicenna) really say this?

The library’s label is Paraphrase or translation. A condensed English of the floating-man passage in the Book of Healing, on the soul. It paraphrases a longer Arabic argument rather than one polished aphorism. The experiment is his. The sentence-shape here is editorial.

Where it comes from

The Book of Healing, Psychology (Kitāb al-Nafs), the floating man

Approximate date: c. 1020s.

How to use it

Someone filling a hospital form in Birmingham lists job, postcode, and next of kin, and notices how much of the word self has become a set of external handles. The floating man asks what would still be affirmed if sight, touch, and those handles went quiet. It does not answer the form, and it asks which part of the answer was only the form.

A mindset reading

A thought experiment is not a proof just because it is vivid, and the question to press is what it assumes: that a mind can consider itself with no sensory content and still be sure of the affirmation. Rejecting that assumption is a serious reply. Treating the story as a meditation script, or as Descartes written early, is not what the passage is doing.

Understand the philosophy

The floating man belongs to Ibn Sina's psychology and to his account of the soul. The key term is the self, the reality that affirms its own existence without perceiving a limb or an outside object. Later readers compare the scene with Descartes, who will not be born for centuries, and the comparison is ours rather than his intention. This English condenses a longer passage and is marked as a paraphrase.

Related

• “Medicine is the science by which we learn the various states of the human body, in health and when not in health, and the means by which health is likely to be lost and, when lost, is likely to be restored.”

  Paraphrase or translation

• “The knowledge of anything, since all things have causes, is not acquired or complete unless it is known by its causes.”

  Paraphrase or translation

• “The necessary existent is that which, when it is assumed not to exist, an absurdity results. The possible existent is that which, when it is assumed either to exist or not to exist, no absurdity results.”

  Paraphrase or translation

Related bias. Confirmation bias. Confirmation bias is the tendency to search for, remember, and accept what supports a view you already like, and to skim past what would hurt it. It is not a claim that every belief is stubborn. It is a pattern in how attention is spent.

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