Avicenna: Essence, Existence and the Soul

“His essence exists.”

Avicenna, The Book of Healing, “On the Soul,” I.1, 15.17–16.17, a passage from the thought experiment; source English translation in Peter Adamson and Fedor Benevich, p. 148. Editorial English rendering of the approved Russian version, not the published English wording. This is what the hypothetical participant affirms about himself, not a report of empirical testing.

About this article

A house plan can be impeccable while the house does not yet exist. This simple difference introduces one of Avicenna's questions: what does it mean to understand what something is, and what does it mean to assert its existence? We will examine essence and existence, possibility and necessity, then turn to the soul and the famous “flying man” thought experiment. Its task is to investigate self-awareness philosophically, not replace observation of the brain or conduct a sensory-isolation experiment. Comparisons with Descartes, Thomas Aquinas and a Buddhist examination of the aggregates show why similar words about the self and necessity need not yield the same conclusion. Contemporary examples distinguish description, actuality and explanation. They belong to our analysis, do not prove Avicenna's metaphysics, and do not require accepting it in advance. Careful reading leaves room both for a coherent argument and for objections to a transition that seems too quick.

I. What is it—and does it exist?

Essence answers what a thing is; existence answers whether it is. In Avicenna this distinction concerns the structure of metaphysics, not merely the everyday difference between a plan and a result. In his study of Avicenna's metaphysics, Amos Bertolacci examines what a thing is and the fact of its existence, including mental and external existence.

On a table lies the drawing of a house not yet built. We can specify its rooms, ceiling heights and windows. We can already disagree about it: one person finds it comfortable, another cramped. Yet no precision of description lets us open its door today. Knowing what we are thinking of and knowing whether it exists outside thought are different tasks.

The example is hypothetical, but the distinction matters to reasoning. We continually confuse possibilities, definitions and facts. Someone describes a just order as though they have established its feasibility. Another clearly imagines a future conversation and thinks they know how the other person will reply. A third can name their profession but cannot explain what their own presence means to them.

The drawing introduces the question without replacing the historical doctrine. It exists as paper or a file. Its content exists as a representation. The house it represents may not exist yet. “This house does not exist” therefore needs qualification: there is no building, but there is a project and an intelligible subject of discussion.

This is not wordplay. It guards against moving between different meanings of an assertion. A project's author says, “We have created a space for meetings.” Perhaps a description has indeed been created. An accessible meeting place, however, requires construction, permissions, resources and working access arrangements. A detailed presentation cannot compensate for their absence.

One might object that “What is it?” already assumes the object's existence. Sometimes our language works that way. But an object may be imaginary, misidentified or discussed as a possibility. The point is not to forbid the question but to specify the domain in which it is asked.

The distinction has a limited use in hypothetical self-description too. Someone says, “I always support those close to me.” This describes a desired or accepted self-image. To establish whether support exists in a particular situation, examine the action. Its presence cannot be deduced from an attractive identity.

Nor should the definition be dismissed: it may indicate how someone intends to act. Intention simply differs from achievement. Distinguishing them gives each its place and reveals the work still missing.

II. Possibility does not mean insignificance

For Avicenna, possible existence does not make a thing insignificant or approximate. Its essence does not, by itself, necessitate its existence. If it exists, its ground remains a question. Bertolacci's metaphysical analysis follows this distinction towards what is necessary in itself and what is necessary through another.

Do not confuse modal status with an observer's confidence. Someone can know reliably that a tree grows in the yard while recognising that it might not have grown. Acknowledging conditions does not make its existence less real. Conversely, strong confidence does not make an event necessary in itself.

A hypothetical team member says, “This result was inevitable.” They may mean it followed regularly from conditions. But several claims can hide here: it followed from specified conditions; we now see its causes; or we are simply ignoring alternatives. These differ, particularly when an explanation informs the next decision.

Suppose a meeting fails. One person misses the message, another does not check the address, and a third assumes everything is agreed. Afterwards, saying nothing else could have happened is easy. It does not establish what actions were available earlier. Knowing the outcome narrows attention to the conditions that produced it.

This everyday example does not apply Avicenna's entire cosmology. It separates the modal question—what is possible or necessary—from a psychological sense of predictability. That sense often makes events seem clearer afterwards than they were to participants.

Recognising dependence raises another question: dependence on what? “Circumstances” is too easily an empty container. In everyday life, identify conditions that can be checked and distinguish them from a proposed ultimate ground belonging to philosophical reasoning.

Explaining the past does not directly establish that future choices are useless. If the meeting failed because of messages, addresses and assumed agreement, those conditions can be changed next time. Even someone who regards the world as strictly causal must explain why their action falls outside the causal sequence. “Everything is conditioned” is not itself an instruction to do nothing. It may direct attention to action as a condition. This is our limited practical argument; it does not settle the historical dispute about freedom in Avicenna's system.

III. A necessary ground is not a larger object

Avicenna's necessary existent does not add an exceptionally powerful thing to a list of things. The question changes: why is there dependent existence, and what ground would not require the same explanation? A few everyday examples cannot reproduce this whole argument.

Dimitri Gutas's survey of Avicenna places it within a system of connected arguments. Learning one term therefore does not establish the entire result. A reader needs the premises, inferential steps and the argument's place in the larger work.

The chief danger is hiding a question inside a definition. Calling a ground “something requiring no ground” leaves us to establish why its existence should be accepted. A definition specifies a proposed status; it need not persuade someone who has not accepted the argument's earlier steps.

We can also ask whether explanation must terminate, what kind of termination is required, and whether the meaning of “cause” changes during the argument. These are substantive philosophical objections. Centuries of discussion do not make them trivial.

Contemporary language often uses “foundation” more freely: “Trust underpins the project,” “Love is the family's foundation,” “Discipline underpins the work.” These useful formulas do not automatically belong to the same metaphysics. Trust depends on behaviour; discipline changes; love requires a particular relationship. None becomes necessary being to strengthen a phrase.

Historical thought retains its dignity when we do not make it decorative. Avicenna asks about existence as such. Someone planning shared work asks about the conditions of its stability. An analogy can connect these questions without erasing their difference in scale.

That scale explains why philosophical reading sometimes yields more precise uncertainty rather than a ready answer. We begin to see which part of a question we have answered and where we have only named the next difficulty.

IV. The soul is not a list of attractive qualities

Today “soul” readily names depth, kindness or a hidden true self. In Avicenna it belongs to philosophical psychology and questions about living beings. Listing feelings and preferences is insufficient for discussing the human soul.

In his study of Arabic and Islamic philosophy of mind, Alfred Ivry examines historical concepts of the soul and cognitive faculties. The context matters: sensation, imagination and thinking were not one undifferentiated interior. This historical scheme, however, is not a contemporary neurobiological model.

When someone says “That is my soul,” they may mean an ethical stance, emotional response, self-awareness or religious belief. Clarify the question before the discussion becomes fruitless. Otherwise one participant discusses immortality, another dignity, and a third the origins of experience.

In a hypothetical conversation, a musician says they put their soul into a performance. A researcher asks what bodily activity makes performance possible. They need not contradict one another: the first describes meaning, the second conditions of the process. But deriving proof of a separate immaterial entity from expressive performance requires another argument.

The reverse transition needs care too. Describing bodily conditions does not automatically exhaust how a performance is experienced or what it means. Knowing an instrument's workings does not explain a particular composition. This does not prove an immaterial soul; it shows that different descriptions do different work.

Philosophical psychology is thus useful first as a discipline of questions. What needs explanation: the ability to act, access to one's condition, personal unity, or knowledge of a general concept? Without distinguishing these tasks, one attractive word answers everything and explains nothing.

V. A person who cannot feel his body

The flying man thought experiment radically changes the conditions. In the version discussed, imagine someone created all at once, without a previous history, deprived of sensory input and with limbs not touching. Would he affirm his own presence without awareness of his body?

In their study of the argument, Peter Adamson and Fedor Benevich translate the relevant passage of “On the Soul” and analyse its purpose. Their reading concerns the soul's essence and involves contested assumptions about access to it. The famous scene is therefore no straightforward laboratory proof that consciousness exists without a brain.

Notice “imagine.” This is not a report about someone actually placed in those conditions. An ordinary person closing their eyes does not qualify: they have memory, bodily states, language and a developmental history. Failing to attend to a body part does not mean it plays no role.

The experiment deliberately removes familiar information to direct attention towards a distinction. Its force depends on what may legitimately be imagined and what conclusions imagination licenses. Readers may reject one of those transitions.

In our own hypothetical example, a spectator does not know how a performance works. They see the play and distinguish it from their seat. Their ignorance does not show that it exists without a stage, lights and actors. This illustrates a possible inferential mistake; it is not a precise refutation of Avicenna's entire position.

To examine the stronger conclusion, formulate a possible bridging premise: everything essential to my existence would have to appear in immediate self-awareness. This is our provisional formulation of a condition for the inference, not a quotation or a new reconstruction of Avicenna. Accepting it gives the body's absence from awareness greater weight. Yet it needs justification: why must a mode of access reveal every condition of existence? Without it, the proposed self-awareness remains significant, while independence requires another argument. Readers can temporarily accept the scene and still stop at its stronger interpretation. The disagreement becomes specific: investigate the connection between awareness and what it permits us to assert about essence.

The difficulty remains open: different ways of accessing something need not imply different ways of existing. Equally, bodily conditions do not settle immediate self-awareness. The experiment's value lies in making us examine this fork, not declaring one branch obvious.

VI. Knowing yourself does not mean knowing everything about yourself

Discussions of self-awareness invite a tempting inference: if I know my presence immediately, I immediately know who I am and why I act. These claims differ. Access to one's experienced condition is not knowledge of its causes or the person's complete essence.

In a scholarly conversation between Peter Adamson and Jari Kaukua, published by Johns Hopkins University Press, self-awareness and its relationship to sensory experience in Avicenna are discussed. It shows that interpreting a historical text remains a matter of reasoned inquiry, not universal agreement among specialists.

A narrower point is useful in everyday life. Someone can be certain they are angry yet mistaken about why. They can feel relief without knowing what changed. They can clearly recognise an intention to help while overlooking that their proposed help inconveniences someone else.

Someone in a hypothetical situation says, “I know myself: I am never envious.” Perhaps they find no such experience now. The general claim that the state is impossible is much stronger. It closes future scrutiny: every uncomfortable feeling must be renamed to preserve the portrait.

Immediacy does not mean infallibility in every respect. Distinguish presence, description, explanation and evaluation. “I am hurt” reports a condition. “Your intention to humiliate me caused it” adds a causal hypothesis about someone else. “Therefore I must retaliate” adds a normative conclusion. One ground does not support the entire chain.

This is our contemporary application, not Avicenna's theory of emotions. It preserves first-person knowledge without extending it indiscriminately. Checking an explanation need not deprive someone of the right to report their experience. We can acknowledge the report and investigate the next step. Respect and precision need not oppose one another.

VII. Imagination cannot replace observation

A thought experiment can test a concept's meaning, a possible consequence or a hidden premise. It does not automatically perform empirical inquiry. Questions about observable processes require information about what actually happens and how that information was obtained.

In his study of Avicenna's natural philosophy, Jon McGinnis shows the historical structure of questions about nature. Avicenna worked with a system of natural and cognitive questions of his time, not just elegant inner scenes. Reducing him to the flying man is as inaccurate as treating his entire work as modern experimental science.

A team hypothetically designing a service imagines an ideal user calmly reading instructions and selecting the right action. This model may expose a logical contradiction in the screen sequence. It cannot establish how many actual people will notice a button or behave when hurried.

Neither method has to demean the other. Without a model, observations may remain disconnected; without observations, a model may become complacent. What result have we obtained: a possible scenario, a rule, measured behaviour, or a confirmed explanation? These cannot all be called “verified.”

Likewise, we can reconstruct a historical argument about the soul accurately, understand its purpose, identify a disputed premise, and still leave today's question of consciousness unresolved. That is not failed reading. It identifies the work the reading accomplished.

Giving thought an unwarranted result weakens it. Debate focuses on a promise it never needed to make. A limited, clearly stated distinction, by contrast, may remain useful even to someone who rejects the later metaphysical conclusion. Precision sometimes begins by reducing a claim.

VIII. Understanding requires the connecting step

We often know an argument's beginning and end without understanding the transition. “Essence differs from existence” is familiar; so is the conclusion about a necessary ground. Without reconstructing the intermediate work, knowing the terminology only resembles understanding.

The study of Avicenna's logic examines inference, definition and demonstration. Our limited point is that a result requires an argument's structure, not merely the right words. We do not reproduce his entire logical apparatus here.

Someone hypothetically knows rest is important and decides to cancel every obligation immediately. Several steps are missing. What condition needs changing? Which obligations exist? What kinds of rest are available? Who is affected? A true general proposition does not automatically determine an action.

Another person knows relationships require trust and concludes that checking agreements is offensive. Yet trust can include clear conditions. They must explain why this particular check destroys rather than supports the relationship. Otherwise “trust” merely occupies the place of a missing argument.

A small practical technique helps with complex philosophy: reconstruct one intermediate proposition in your own words. If you cannot, do not fill the gap with the author's name. Mark what remains unclear and return to the passage. Stopping there saves later effort: an application will not rest on a transition still misunderstood.

Try the reverse test too. Can you find a case where the starting propositions hold but your chosen conclusion does not? If so, another condition may be needed. This cannot settle every philosophical dispute, but it can reveal an overextended inference.

Respect for Avicenna then means walking part of the path rather than repeating a powerful conclusion. His system need not immediately become ours. First distinguish recognising a term from reconstructing an argument.

The language of confidence needs its own check. “I can explain this,” “This explanation seems suitable,” and “I have grounds to exclude alternatives” report different results. Equal confidence forces listeners to guess the support available. Clarify without lengthy qualifications: name one fact, one connecting step and one important unknown. We know the message was unread; we suppose that explains the person's absence; we do not yet know whether other reasons existed. This lets us refine an explanation rather than merely defend it.

IX. One self-awareness, several philosophical tasks

Self-awareness becomes clearer when we distinguish the question it is meant to answer. Avicenna introduces the flying man within an investigation of the soul. In Part IV of Descartes's Discourse on the Method, the thinker emerges after doubt about the senses, reasoning and dreams. An imagined absence of bodily perception and methodological doubt are different conditions of inquiry.

Both attempt to isolate self-certainty distinct from a list of perceived body parts. But acknowledging an experience of self leaves open what follows from it. It does not reveal the soul's entire nature, its relation to the body or the conditions of immortality. Modern scholars of Avicenna therefore examine individual inferential steps. No unsupported claim of historical influence is needed: analytical comparison suffices to reveal the different tasks.

A change of text changes an objection's meaning too. In SN 22.59, bodily form, feeling and the other aggregates are examined for whether they can be appropriated as a stable self. This is not the same thought experiment with a different outcome: the method and liberating aim change. The Buddhist text does not supply Avicenna's missing empirical test. It shows another way of asking about oneself without turning experienced presence into possession of an immutable essence.

Necessity offers a separate comparison. Aquinas's third way begins with things coming into and passing out of existence. Avicenna's distinction between what is possible in itself and necessary through a cause organises another analysis. Similar vocabulary requires reading the transitions, not merging the arguments.

Return to the house plan. Calling it “necessary” may mean necessary for our purpose; necessary existence in Avicenna means something quite different. “I know myself” may likewise mean experienced presence, biographical knowledge or philosophical knowledge of the soul. Distinguishing these assertions reduces the pressure to choose between unconditional assent and rejecting the author's whole thought.

X. Between a clear concept and an open question

Avicenna does not offer convenient freedom from conditions. His distinctions demand closer attention to what is known and how. Essence does not automatically certify external existence. Reliable observation does not make its object necessary in itself. Self-awareness does not instantly explain the whole person.

The questions remain connected without becoming identical. A metaphysical argument needs its own grounds. A historical text needs accurate reading. A contemporary claim about body and consciousness needs relevant research. An everyday decision needs information about circumstances and consequences for participants.

Keeping these boundaries can seem like losing depth. We want one great idea to explain the world, the person and a particular conflict. That reach easily comes at the expense of precision. The more a formula promises, the less room remains to notice where it works.

Return to the drawing. Its description can be excellent while construction has not begun. There is no reason to destroy the description; name the next task. Similarly, an argument can reveal a significant distinction without providing a final answer. Reading has not been wasted.

Mature understanding sometimes begins with saying: here I know the subject; here I understand the transition; here I accept the premise; here I remain unconvinced. This is slower than ready agreement but permits real participation in reasoning.

Avicenna remains a conversation partner because his thought allows this work. We can decline his final answer while seeing our own question more clearly. Between definition and existence, body and self-access, imagination and observation lies a space for attentive inquiry, not a void.

What this means in practice

Begin practical reading by distinguishing description from fulfilment. Choose one project, promise or self-description. You need not turn your whole life into an exercise: a bounded subject that raises a real question is enough.

Write down what is described: “We are creating a place where people can talk calmly.” Then name what exists already: premises, agreements, a schedule, participants, a privacy rule. Next identify what exists only as intention. This does not devalue the project; it shows the conditions for action.

Then consider necessity. What must happen for the plan to succeed? What is merely customary? Is another arrangement possible? A hypothetical meeting may need an agreed time, but not one particular app. Confusing a condition with a habit makes the solution more rigid than necessary.

Now examine self-knowledge. What do you notice directly? What do you explain tentatively? What unverified information about another person are you adding? “I feel anxious” need not disappear while its cause remains unknown. Acknowledging uncertainty helps clarify the situation without denying the experience.

Finally, test one application of an analogy. Why does it seem apt? What difference does it preserve? Where does it fail? A drawing and a house distinguish intention from fulfilment without explaining every relation between essence and existence. The flying man raises self-awareness without replacing facts about a living body.

A small result can suffice: a clarified promise, an identified condition, a marked premise or a better question. You need not immediately accept a metaphysical system or define your nature conclusively. Philosophical reading may change one transition in reasoning.

That is the practical measure: has reading a major thinker reduced unnoticed substitutions? If a plan is no longer called a result, confidence necessity, or experience knowledge of every cause, space opens for the next action. You must still choose it yourself.

Key quotation

“I think; therefore I exist.”

René Descartes, Discourse on the Method, IV; source English translation by John Veitch. Editorial English rendering of the approved Russian version, not the published English wording. The comparison clarifies self-certainty while retaining the different tasks of Descartes and Avicenna.

Connections across traditions

These are our analytical comparisons. Historical influence is not asserted without supporting evidence.

Subject	Positions and supporting texts	What can be compared	Where the boundary lies
Essence and actuality	Avicenna: metaphysics — Spinoza, Ethics I, definitions and Proposition 29	Understanding a thing is connected with asking about the ground of its existence.	Avicenna's modal system differs from Spinoza's necessity; possibility cannot be treated as the same term in both.
Possibility and necessity	Avicenna: possible in itself — Aquinas, I q.2 a.3	Inquiry asks whether the finite suffices to explain existence.	The third way starts from arising and passing away; its transitions differ from Avicenna's construction.
Self-certainty	Flying man, “On the Soul” I.1 — Descartes, Discourse IV	The thinker's presence differs from a list of sensory data.	Absent sensation and methodological doubt are different conditions; historical influence is not established here.
Knowing and appropriating oneself	The flying man — SN 22.59	Self-experience requires separate investigation.	Avicenna seeks a characteristic of the soul; the sutta examines not appropriating the aggregates as self. No identical soul is postulated.
Confidence and argument	Avicenna: reconstructing the argument — Al-Ghazali, §§6–24	Strong confidence differs from justification of an inference.	Al-Ghazali's crisis and restored certainty are religious testimony, not an extension of Avicenna's experiment.

Sources

Primary texts, normative documents and research commentary are distinguished in the descriptions. A reference study does not become a primary text through this heading.

Amos Bertolacci. Ibn Sina's Metaphysics. Stanford Encyclopedia of Philosophy. Essence/existence, possibility/necessity.
Dimitri Gutas. Ibn Sina. Stanford Encyclopedia of Philosophy. The systematic context of philosophy and cognition.
Alfred Ivry. Arabic and Islamic Psychology and Philosophy of Mind. Stanford Encyclopedia of Philosophy. Historical philosophical psychology.
Peter Adamson, Fedor Benevich. The Thought Experimental Method: Avicenna's Flying Man Argument. Journal of the American Philosophical Association, 2018. Translation of the “On the Soul” passage, assumptions and objections.
Peter Adamson, Jari Kaukua. Journal of the History of Philosophy podcast transcript. Johns Hopkins University Press. Discussion of self-awareness and experience in Avicenna.
Jon McGinnis. Ibn Sina's Natural Philosophy. Stanford Encyclopedia of Philosophy. Context of inquiry into nature.
Riccardo Strobino. Ibn Sina's Logic. Stanford Encyclopedia of Philosophy. Concepts, definitions and demonstration.
René Descartes. Discourse on the Method, IV; English translation by John Veitch. Primary text: doubt and the thinker's self-certainty. Text and passage used.
Thomas Aquinas. Summa Theologiae, I, q.2, a.3, the third way. Primary text: possibility and necessity; New Advent English edition. Text and passage used.
SN 22.59, Pañcavaggi / Anattalakkhaṇa Sutta; translated by Thanissaro Bhikkhu. Primary Buddhist text: impermanence of the five aggregates and not appropriating them as self. Text and passage used.
Spinoza. Ethics, I, Definitions III–V and Propositions 15, 18, 29; English translation by R. H. M. Elwes. Primary text: substance, modes, immanent causation and necessity. Text and passages used.
Al-Ghazali. Al-Munqidh min al-Ḍalāl / Deliverance from Error; English translation by Richard J. McCarthy. Primary text: certainty, logic, knowledge of the path and its enactment; selected §§6–24, 37–45, 80–85. Text and passages used.

About the authors

Andrey Zarinsh is the author and founder of United Wisdom. He explores inner transformation, the unity of traditions, intercultural dialogue and contemporary spiritual discipline. Instagram: @andrey.zarinsh.

Maria Evilkut is the co-author of United Wisdom. Alongside her research, she seeks to test these ideas in practice and observe how principles of unity and mutual understanding work in real life between people and cultures. Instagram: @ilkutki.