The History and Precision of the Most Important Word in Philosophy of Mind, and its Definition in the Sensible Universe Model
“There is something it is like to see red. There is something it is like to feel pain. There is something it is like to taste coffee, to hear a minor chord, to smell rain on warm pavement. This ‘something it is like’ — this irreducible interior dimension of experience — is what philosophers call a quale. And it is, without exaggeration, the most important unsolved problem in all of science and philosophy combined.”
— Thomas Nagel, What Is It Like to Be a Bat?, 1974
I. The Latin Seed — Qualis
The word quale comes from the Latin interrogative pronoun qualis: of what kind? what sort? The same root that gives English the word quality, and that gives Spanish cualidad and cual. In classical Latin, qualis asked about the essential nature of a thing — not whether it exists, not how large it is, but what kind of thing it is. Quale nomen tibi est? What kind of name do you have? Qualis homo es? What kind of man are you?
The word carries within it a structural presupposition that philosophy has taken two thousand years to fully unpack: that there is a difference between a thing and the kind of thing it is. Between the rose and the redness of the rose. Between the fire and the heat of the fire. Between the sound wave and the experience of hearing. This gap — between the physical event and the qualitative character of experiencing it — is the gap the word quale has always pointed toward, even before philosophy gave it technical precision.
The ancient Greeks had their own ways of gesturing at the same territory. Aristotle’s distinction between the sensible form (the form without the matter, received by the sense organ) and the physical object was an early attempt to account for the fact that when the eye receives the form of the red apple, it does not thereby become red. Something is transmitted; something is received; what arrives in the perceiver is not the object but something about the object — its qualitative character, its what-it-is-like-ness.
“The sense-faculty in actuality is the sensible object in actuality. But there is no absolute identity between them: the faculty is potentially what the object is actually. The wax receives the seal of the signet-ring without the iron or gold of which the ring is made.”
— Aristotle, De Anima II.12, c. 350 BCE
Aristotle’s wax is one of the most precise formulations available in ancient thought: the wax receives the form — the what-it-is-like-ness — without receiving the matter. The shape arrives; the gold does not. And the shape that arrives is not nothing: it is the form, the quale, the experiential character of the object — real in the wax, real in the perceiver, without being made of the same stuff as the thing perceived.
This distinction — between the physical cause and the qualitative experience — was the seed that would take two millennia to germinate into the full philosophical problem of qualia. Along the way, every major figure in the history of philosophy was growing the same plant without quite agreeing on what species it was.
II. The Early Modern Period — Primary and Secondary Qualities
The scientific revolution of the seventeenth century drew a line that would prove enormously consequential for the history of consciousness studies. Galileo, Descartes, and Locke distinguished between two kinds of properties: primary qualities, which belong to objects themselves — shape, size, number, motion — and secondary qualities, which are not in the object but are produced in the perceiver by the object’s action on the sense organs. Colour, sound, taste, smell, warmth: these are, in this framework, not properties of things but responses of minds to things.
“Let us suppose it were possible that the Sun had no more light than the weakest Star; the Idea it produces in us would be no bigger, than what the least Star does. Colours are not in Objects, but are certain Dispositions of them to produce Sensations in us.”
— John Locke, An Essay Concerning Human Understanding, 1690
Locke’s distinction was intended to align philosophy with the new mechanical science: the real world is the world of primary qualities, measurable and mathematical; secondary qualities are the mind’s contribution to experience. But Locke’s own honesty got in the way of a clean solution. He admitted that we have no idea what primary qualities are like in themselves — we only know them through the secondary qualities they produce in us. The world-in-itself, stripped of all qualitative experience, is something we cannot directly access.
George Berkeley took this admission to its logical extreme: if we only ever know secondary qualities, and primary qualities are always given through secondary ones, then we have no reason to posit a world behind our experience at all. Esse est percipi — to be is to be perceived. The world is the world of experience; there is no meaningfully distinct world behind it. Berkeley’s idealism was, among other things, the first sustained argument that experience is ontologically primary — a position the Sensible Universe Model will eventually formalize in its own terms.
“It is indeed an opinion strangely prevailing amongst men, that houses, mountains, rivers, and in a word all sensible objects have an existence natural or real, distinct from their being perceived by the understanding. But with how great an assurance and acquiescence soever this principle may be entertained in the world, yet whoever shall find in his heart to call it in question may, if I mistake not, perceive it to involve a manifest contradiction.”
— George Berkeley, A Treatise Concerning the Principles of Human Knowledge, 1710
Hume refined the problem further. He distinguished between impressions — the vivid, immediate data of experience — and ideas — the fainter copies of impressions that populate thought and memory. What Hume called impressions are what later philosophy will call qualia in their most direct form: the immediate qualitative character of experience, prior to any interpretation or inference. And Hume made the observation that would become the foundation of the Hard Problem: no amount of reasoning about physical causes can produce the impression itself. The impression is simply given, or it is not given.
“When I enter most intimately into what I call myself, I always stumble on some particular perception or other, of heat or cold, light or shade, love or hatred, pain or pleasure. I never can catch myself at any time without a perception.”
— David Hume, A Treatise of Human Nature, 1739
Kant attempted the reconciliation. In his framework, the qualitative character of experience is not in the object, not purely in the subject, but in the necessary forms through which any possible experience must be structured: space, time, the categories of the understanding. The quale of experience, for Kant, is not arbitrary: it is constrained by the transcendental structures of sensibility. But Kant also insisted that the thing-in-itself — the Ding an sich — is permanently inaccessible. We experience phenomena, not noumena. The qualitative world is the only world we have access to.
The early modern period, taken as a whole, identified the problem with extraordinary precision: there is a gap between the physical world and the world of experience, the gap cannot be bridged by describing the physical world in more detail, and the world of experience has its own irreducible character that no physical description captures. What it lacked was a word precise enough to hold the concept. That word arrived in 1929.
III. C.I. Lewis and the Technical Birth of Quale
The first technically precise use of the word quale in the modern philosophical sense appears in Clarence Irving Lewis’s Mind and the World-Order, published in 1929. Lewis was an American pragmatist philosopher working at Harvard, and his project in that book was to give a rigorous account of the relation between immediate experience and conceptual knowledge. He needed a word for the immediate qualitative character of experience — the what-it-is-like-ness — that was prior to any interpretation, any conceptual framing, any inference about what caused it.
“There are recognizable qualitative characters of the given, which may be repeated in different experiences, and are thus a sort of universals; I call these qualia. But although such qualia are universals, in the sense that they are recognized from one to another experience, they must be distinguished from the properties of objects. Qualia are subjective; they have no names in ordinary discourse and are not even, in general, sufficiently noticed to be distinguished and identified. They are merely the recognizable qualitative characters of what is given.”
— C.I. Lewis, Mind and the World-Order, 1929
Lewis’s definition is remarkable for what it gets right and for what it leaves unresolved. He gets right that qualia are the recognizable qualitative characters of immediate experience — the redness of red, the painfulness of pain — and that they are distinct from properties of objects. He recognizes that they are rarely explicitly named in ordinary language because they are so immediate and so constant that we look through them rather than at them. What he leaves unresolved is the ontological status of qualia: they are ‘subjective,’ but what does that mean? Are they mental states? Brain states? Something else entirely?
Lewis’s introduction of the term opened a space that the rest of the twentieth century would fill with increasingly precise and increasingly contentious proposals. The word caught on because it named something everyone knew about but had no single precise word for. Once named, the problem could be examined with new rigour.
Wilfrid Sellars and the Myth of the Given
Wilfrid Sellars attacked Lewis’s framework from an angle that would prove enormously influential. The Myth of the Given, Sellars argued, is the assumption that experience provides an epistemologically secure foundation — a bedrock of immediately known qualitative facts — that can serve as the basis for all other knowledge. Sellars denied this: all experience, including the most immediate seeming, is already conceptually structured. There is no pre-conceptual given.
“The essential point is that in characterizing an episode or a state as that of knowing, we are not giving an empirical description of that episode or state; we are placing it in the logical space of reasons, of justifying and being able to justify what one says.”
— Wilfrid Sellars, Empiricism and the Philosophy of Mind, 1956
Sellars’s critique raised a question that haunts the history of qualia: if all experience is conceptually structured, are qualia — conceived as pre-conceptual qualitative data — even coherent? Or is the concept of a purely immediate, pre-conceptual quale itself a philosophical fiction? This debate between the ‘given’ and the ‘conceptualized’ runs through the entire subsequent history. The Sensible Universe Model will eventually offer a structural resolution: qualia are not pre-conceptual fictions, but neither are they fully reducible to conceptual content. They occupy a distinct ontological register: the qualitative field of M₄.
IV. Thomas Nagel — What Is It Like to Be a Bat? (1974)
The single most influential paper in the history of consciousness studies is probably Thomas Nagel’s ‘What Is It Like to Be a Bat?’ published in The Philosophical Review in 1974. Its importance lies not in any positive doctrine it defends but in the precision with which it defines the problem.
Nagel’s argument is simple and devastating. Bats navigate by echolocation — they emit high-frequency sounds and perceive the world through the reflections. We can describe this system in complete functional and physical detail: the frequency ranges, the neural processing, the behavioral outputs. But none of this description tells us what it is like to be a bat. Is there something it is like? Is the bat’s world of sonar-echoes qualitatively rich in the way that our visual world is qualitatively rich? We have no idea. And crucially, Nagel argues, no amount of additional physical or functional description will give us any idea. The gap between physical description and qualitative experience is not a gap of missing data: it is a structural gap between two different kinds of reality.
“If physicalism is to be defended, the phenomenological features must themselves be given a physical account. But when we examine their subjective character it seems that such a result is impossible. The reason is that every subjective phenomenon is essentially connected with a single point of view, and it seems inevitable that an objective, physical theory will abandon that point of view.”
— Thomas Nagel, What Is It Like to Be a Bat?, 1974
Nagel’s formulation — ‘there is something it is like’ — became the standard philosophical shorthand for the what-is-it-like-ness of experience. A thermostat responds to temperature, but there is presumably nothing it is like to be a thermostat. A human being responds to temperature, and there is definitely something it is like — the felt warmth, the specific qualitative character of heat on skin. The quale of warmth is not the temperature reading; it is the experience of that temperature from the inside.
What Nagel established as his central point is that the existence of qualia is incompatible with a purely third-person, objective account of the world. Qualia are essentially first-person. They are accessible only from a point of view. And any theory that eliminates the first person — that tries to describe the world without any perspective — automatically eliminates qualia, not by explaining them but by failing to give them a place to stand. The first-person is not a methodological preference: it is an ontological necessity.
V. Frank Jackson — Mary’s Room (1982)
Frank Jackson’s 1982 paper ‘Epiphenomenal Qualia’ introduced one of the most discussed thought experiments in the history of philosophy: the case of Mary the color scientist.
Mary is a brilliant scientist who has lived her entire life in a black-and-white room. She knows everything there is to know about the physics of color, the neurophysiology of color perception, the complete functional story of how the visual system processes wavelengths of light and produces responses in the brain and behavior. She has, in Jackson’s stipulation, complete physical knowledge of color. And yet — the thought experiment asks — when Mary leaves her room and sees a red tomato for the first time, does she learn something new?
“It seems just obvious that she will learn something about the world and our visual experience of it. But then is it not clear that her previous knowledge was incomplete? But she had all the physical information. Ergo there is more to have than that, and physicalism is false.”
— Frank Jackson, Epiphenomenal Qualia, 1982
Jackson’s argument is the knowledge argument: complete physical knowledge does not entail complete knowledge of qualitative experience. Mary knew everything about the physics of red. She did not know — could not know, until she saw it — what red looks like. The quale of red is not contained in any physical description, however complete. Therefore qualia are not physical facts.
The Mary case became one of the most argued-over thought experiments in philosophy precisely because it focuses the problem with such clarity. The responses it generated are as illuminating as the case itself. Physicalists argued that Mary does not learn a new fact — she merely gains a new ability (the ability-hypothesis of Lewis and Nemirow). Others argued that she acquires a new concept, not a new fact. Daniel Dennett argued that the intuition that she learns something is simply mistaken — a failure of imagination, not an insight into the nature of reality. And Frank Jackson himself later recanted, arguing that qualia are after all physical facts that we describe using special phenomenal concepts.
But the case itself — independent of any of these responses — captures something that the Sensible Universe Model regards as structurally correct: the quale of seeing red is not reducible to any functional or physical description of the process of seeing red. The quale is precisely the what-it-is-like-ness of the experience: the specific, irreducible, non-interchangeable qualitative character of this encounter between a Witness and the world.
VI. David Chalmers — The Hard Problem of Consciousness (1995)
David Chalmers gave the problem of qualia its most influential modern framing in his 1995 paper ‘Facing Up to the Problem of Consciousness’ and his 1996 book The Conscious Mind. Chalmers drew the distinction that has organized the field ever since: the easy problems of consciousness and the hard problem.
The easy problems — which Chalmers readily acknowledges are not actually easy — are problems of function: how does the brain integrate information? How does it discriminate stimuli and respond appropriately? How does it report on its own states? These are problems where we know in principle what kind of answer we are looking for: we look for a mechanism that performs the function. Given enough neuroscience and cognitive science, we expect to solve them.
“The really hard problem of consciousness is the problem of experience. When we think and perceive, there is a whir of information processing, but there is also a subjective aspect. As Nagel has put it, there is something it is like to be a conscious organism. This subjective aspect is experience. When we see, for example, we do not just process information about the shapes and colors in the environment; we also have an experience of what it is like to see that red, that blue.”
— David Chalmers, Facing Up to the Problem of Consciousness, 1995
The hard problem is the problem of experience itself. Why does any physical process give rise to subjective experience? Why is there something it is like to be a conscious organism rather than nothing? This question, Chalmers argues, is not answered by explaining the functional mechanisms of consciousness — even a complete functional account would leave the question open. A system could, in principle, perform all the relevant functions without there being any subjective experience. This possibility — the philosophical zombie — reveals the structural gap: function and experience are not the same thing, and explaining one does not automatically explain the other.
Chalmers’s formulation is important not because it resolves the problem but because it makes the problem precise. Before him, many philosophers and scientists conflated the easy and hard problems and thought that progress on the easy problems was progress on the hard one. After him, the distinction has become standard: the hard problem is structurally different from the easy ones, and any account that does not address the hard problem directly has simply changed the subject.
The Explanatory Gap
Joseph Levine independently identified what he called the explanatory gap: even if we know that a particular brain state is identical with a particular qualitative experience, we do not understand why that brain state should give rise to that particular experience rather than some other, or no experience at all. The gap is not between what we know and what we would know if we knew more: it is between the physical description and the qualitative fact, a gap that persists even when the physical description is complete.
“Even if it is true that pain is identical to C-fibre firing, we do not understand why C-fibre firing should feel the way pain does. The identity may be true, but it remains unexplained. The explanatory gap is real.”
— Joseph Levine, Materialism and Qualia: The Explanatory Gap, 1983
The explanatory gap, the knowledge argument, the hard problem: these are three different formulations of the same structural observation. Qualitative experience — the what-it-is-like-ness of consciousness, the quale — is not logically entailed by any description of physical or functional states. The gap is not a gap of missing information. It is a gap of kind. And this gap is what makes the problem of qualia the central unsolved problem in all of philosophy and science.
VII. Ned Block — Phenomenal and Access Consciousness
Ned Block introduced a distinction that has become indispensable in the field: the distinction between phenomenal consciousness and access consciousness. Phenomenal consciousness is what we have been calling quale: the felt, experiential character of mental states, the what-it-is-like-ness. Access consciousness is the functional availability of information to reasoning, reporting, and behavioral control — whether a state’s content is ‘poised’ for use in inference and the guidance of action.
“A state is access-conscious if it is poised for direct use in reasoning, reporting, and the guidance of action. A state is phenomenally conscious if there is something it is like to be in it. These two notions come apart. There is access without phenomenality, and perhaps phenomenality without access. The confusion between them is a source of endless muddle in consciousness studies.”
— Ned Block, On a Confusion About a Function of Consciousness, 1995
Block’s distinction is crucial because it reveals that many debates about consciousness have been conducted at cross-purposes. Scientists studying the neural correlates of consciousness are often studying access consciousness: they look for the neural signatures that make information available for report. But what they may or may not be capturing is phenomenal consciousness: whether there is something it is like. The two can come apart. There is access without phenomenality in the overflow debates about unconscious information processing — information that is integrated and used without any accompanying qualitative experience. And there may be phenomenality without access — phenomenal states that exist but cannot be reported or utilized.
The importance of Block’s distinction for the Sensible Universe Model is direct: it maps cleanly onto the distinction between the three states of consciousness. Access consciousness corresponds to the Consciente register — information available to the Witness. Phenomenal consciousness (the quale) is present in all three registers: the quale exists in the Subconsciente and Inconsciente as real qualitative content regardless of whether the Witness is currently accessing it. The Subconsciente has phenomenality without access. The Consciente has both. And the Inconsciente is the pre-personal stratum where GRAVIS was deposited before any access-system existed.
VIII. Daniel Dennett — The Eliminativist Challenge
No account of the history of qualia would be complete without Daniel Dennett, who has spent forty years arguing that qualia, as the term is typically understood, do not exist. Dennett’s position is not that there is no experience — he does not deny that you are reading these words and that there is a process occurring — but that the philosophical concept of quale is incoherent: it refers to a mysterious, ineffable, intrinsically private property that nothing could possibly have.
“Qualia are supposed to be ineffable, intrinsic, private, and directly apprehensible. I claim that there are no such properties. The concept of qualia is a philosopher’s concept: it is built up by abstracting away everything we could actually say or measure about experience until nothing is left but an empty place-holder. And then people are astonished that the place-holder cannot be filled.”
— Daniel Dennett, Quining Qualia, 1988
Dennett’s challenge is serious and deserves a serious response. His argument is that our intuitions about qualia are systematically unreliable: we think we have immediate, incorrigible access to our own qualitative states, but in fact our introspective reports are constructed, post-hoc, theory-laden, and subject to all the errors that attend any other cognitive process. The felt certainty that there is ‘something it is like’ may itself be a cognitive illusion.
The Sensible Universe Model does not accept Dennett’s eliminativism, but it takes his critique seriously enough to propose a different architecture. The problem with the traditional concept of quale is precisely what Dennett identifies: it is defined by what it is not — not physical, not functional, not accessible, not nameable — until it becomes a pure mystery. The SUM response is to give qualia a positive structural definition rather than a negative one. The quale is not defined by its ineffability but by its specificity: the precise, non-interchangeable qualitative mark that a witnessed encounter deposits in the field M₄. This is not mysterious; it is topological.
Dennett is right that there are no ghostly ineffable properties floating free of any physical or functional grounding. He is wrong that this means qualia do not exist. Qualia exist as qualitative events in the conscious field — real, structured, causally active, and in principle empirically investigable — even if they are not the disembodied Cartesian properties that some philosophers have imagined.
IX. The Neuroscience Approaches — Correlates, Integration, and Predictive Processing
Neural Correlates of Consciousness
Francis Crick and Christof Koch proposed the framework of neural correlates of consciousness (NCCs) as an empirical research program: rather than solving the hard problem directly, identify the minimal neural conditions that are sufficient for a specific conscious experience. If we can find the NCC for the redness of red — the specific neural activity that is both necessary and sufficient for the quale — we have at least located where in the brain qualia happen.
“The neural correlate of consciousness is the minimal neuronal mechanisms jointly sufficient for any one specific conscious percept. Finding the NCC is a tractable scientific problem. Explaining why the NCC produces the percept is, we acknowledge, a different and much harder problem.”
— Francis Crick & Christof Koch, Towards a Neurobiological Theory of Consciousness, 1990
The NCC program has produced an enormous amount of valuable research. It has identified candidate regions and dynamics — the thalamocortical system, gamma-band oscillations, posterior cortex activity — that reliably correlate with conscious reports. But Crick and Koch themselves were honest about the limits: finding the NCC does not solve the hard problem. It tells us where the quale happens, not why that neural process produces this qualitative experience rather than another, or no experience at all.
Integrated Information Theory — Giulio Tononi
Giulio Tononi’s Integrated Information Theory (IIT) is the most mathematically ambitious attempt to give qualia a physical basis. Tononi proposes that consciousness is identical with integrated information, measured by a quantity he calls phi (Φ). A system is conscious to the degree that it integrates information irreducibly — that is, to the degree that the information generated by the system as a whole exceeds the information generated by its parts. The intrinsic causal power of the system is what constitutes its consciousness.
“Consciousness is identical to a particular type of information: the information generated by a system above and beyond its parts. This information has a specific structure — it is the intrinsic, irreducible causal power of the system. Phi measures this. Where there is high phi, there is rich consciousness. Where phi is zero, there is no experience.”
— Giulio Tononi, Consciousness as Integrated Information, 2004
IIT has the virtue of taking the qualitative character of experience seriously and attempting to derive it from physical structure. But its critics note that it seems to attribute consciousness to systems that we have no intuitive reason to think are conscious — including certain simple networks with high phi — while potentially denying it to systems, like the cerebellum (which has massive neural architecture but low integration), that seem more likely to contribute to experience. More fundamentally, IIT still faces the hard problem: even if phi measures something real about information integration, it does not explain why high phi should feel like anything.
Predictive Processing — Karl Friston
Karl Friston’s free energy principle and predictive processing framework offers a radically different approach: the brain is not a passive receiver of sensory information but a prediction machine that continuously generates models of the world and updates them based on prediction error. Consciousness, in this framework, is the process of active inference: the brain’s best guess about the causes of its sensory input, refined by the difference between prediction and reality.
“Perception is not the passive registration of the world. It is a controlled hallucination: the brain’s best hypothesis about the causes of its sensory signals, constrained but not determined by those signals. What we experience is not the world but the brain’s model of the world.”
— Karl Friston, The Free-Energy Principle, 2010
Friston’s framework is extraordinarily powerful as an account of the dynamics of perception and cognition. But it faces the same structural problem as all other functional accounts when it comes to qualia: it explains what the brain does without explaining why doing it feels like anything. The predictive processing account of seeing red tells us why the brain generates and updates a model of red wavelengths. It does not tell us why that process is accompanied by the specific qualitative experience of redness. The functional account is complete; the qualitative fact is missing.
X. The Phenomenological Tradition — The Interior Description
While analytic philosophy was arguing about the logical status of qualia, the phenomenological tradition was doing something different: describing them from the inside with systematic precision. This tradition, running from Husserl through Heidegger, Merleau-Ponty, Sartre, and Stein, produced an extraordinarily detailed cartography of the qualitative field of experience — without the debate about whether qualia are reducible to physical facts, because the phenomenological method refuses to begin from the physical description at all.
Husserl — Intentionality and the Structure of Experience
Edmund Husserl’s phenomenology begins with a simple but radical observation: every conscious act is intentional — it is always directed at something, always experience of something. The quale of seeing the red apple is not a free-floating quality; it is the qualitative character of this act of seeing, directed at this object. The intentional object is not the physical apple but the apple as experienced, the apple as it presents itself to this consciousness in this moment.
“Consciousness is always consciousness of something. The stream of consciousness is not a sequence of inner states closed off from the world; it is a stream of acts directed at objects, constituting their meaning through that directedness.”
— Edmund Husserl, Ideas I, 1913
Husserl’s intentional analysis gives qualia their proper context: they are not isolated data points but aspects of intentional acts, structured by the relation between the act and its object. The redness of red is not the redness in isolation; it is the redness as it presents itself in this act of seeing this red thing in this context. The quale is always embedded in an intentional structure, always more than a bare sensation.
Merleau-Ponty — The Lived Body
Maurice Merleau-Ponty’s contribution is to situate qualia in the lived body rather than in a disembodied consciousness. The body is not an object among other objects in the world; it is the vehicle of being-in-the-world, the medium through which we have a world at all. The qualitative character of experience is always already bodily: the redness of red is not a property of a disembodied mind encountering wavelengths; it is the quality that a body with these particular sense organs has when it encounters that light.
“The body is not in space: it inhabits space. It is not beside the world: it is in the world. Our bodily experience of movement is not a particular case of knowledge: it provides us with a way of access to the world and the object, a ‘praktognosia’ which has to be recognized as original.”
— Maurice Merleau-Ponty, Phenomenology of Perception, 1945
Merleau-Ponty’s lived body is the SUM’s M₄ field in embodied form: the totality of qualitative existence, including the pre-reflective, pre-conceptual dimension that Husserl called passive synthesis and that the SUM calls the Subconsciente register. The body knows things the conscious mind has not articulated; the qualitative field is always larger than the Witness’s current scope. The phenomenal quality of experience is not added to the body from outside; it is the body’s own way of being in the world.
William James — The Stream of Consciousness
William James, writing at the intersection of philosophy and the new psychology, introduced the concept of the stream of consciousness: experience is not a series of discrete events but a continuous flow, always already in motion, with each moment shading into the next. The qualitative character of any moment in the stream is partly constituted by what came before and what is anticipated next.
“Consciousness does not appear to itself chopped up in bits. Such words as ‘chain’ or ‘train’ do not describe it fitly as it presents itself in the first instance. It is nothing jointed; it flows. A ‘river’ or a ‘stream’ are the metaphors by which it is most naturally described.”
— William James, The Principles of Psychology, 1890
James’s stream prefigures what the SUM will formalize as the Nunc Stans (the living present) and as qualitative time (τ): the temporal dimension of experience is not clock time but the thick, flowing, contextually saturated time of lived experience. The quale of any moment is not a point in time but a wave that carries the resonance of what came before and the anticipation of what comes next. Qualia are temporal through and through.
XI. The Sensible Universe Model — Quale and Qualia Precisely Defined
The history just traced reveals a consistent pattern: every serious attempt to engage with qualia — from Aristotle’s wax to Nagel’s bat, from Jackson’s Mary to Chalmers’s zombie, from Husserl’s intentionality to Merleau-Ponty’s lived body — identifies the same structural reality from a different angle. Something is present in conscious experience that is irreducible to any physical, functional, or third-person description. That something is immediate, specific, non-interchangeable, and real. It is the what-it-is-like-ness — the precisely this of every encounter with reality.
What the tradition has lacked is a structural framework that gives qualia a positive definition — not what they are not (not physical, not functional, not reducible) but what they are, in structural terms that are both philosophically rigorous and empirically investigable. The Sensible Universe Model proposes that framework. It does so by drawing on the full tradition, correcting specific errors, and introducing two formal concepts that the tradition did not have: the distinction between Quale (singular) and Qualia (the crystallized field), and the concept of the QQP (Quale Quality Pin) as the topological marker that qualia leave in the field M₄.
Quale — The Singular Qualitative Information
| Quale (SUM definition) | The particular, precise, and individual information of a specific quality — the what-it-is-like-ness of this encounter, irreducible to any other. A kiss. A white wool tunic. A sword. The smell of bread from a childhood kitchen. The sound of a child’s voice in the distance. Each quale is singular and non-interchangeable: not the concept of kissing but the quale of this kiss; not the concept of red but the quale of this red at this moment in this light. The quale is the mark that a witnessed encounter leaves in the qualitative field M₄ — precise, topological, real. |
The SUM definition of quale is both more specific and more structural than the standard philosophical usage. In standard usage, quale refers to the phenomenal character of any experience — the redness of red, the painfulness of pain — but often without specifying what that character consists in or how it is structured in the field of experience. The SUM definition specifies: the quale is the precise, non-interchangeable mark left by a specific encounter. Not the category ‘red’ but the specific QQP — Quale Quality Pin — of this specific encounter with this specific shade of this specific thing at this specific moment.
This specificity is what makes the quale irreducible. It is not reducible to any description because descriptions operate through universals and categories, while the quale is irreducibly particular. We could have every neural map in the world and still not be able to explain why that map corresponds to a unique quality of experience — with a specific and particular quale that is not equivalent to any other. The map is real. The territory is more. The quale is the territory.
The QQP — Quale Quality Pin
| QQP — Quale Quality Pin | The topological marker that a witnessed quale deposits in the field M₄. The QQP is the specific, irreplaceable impression that a genuine encounter leaves in the qualitative field — equivalent to a fingerprint, but qualitative rather than physical. Each QQP is unique to this Witness, this moment, this encounter. The network of QQPs accumulated over a lifetime is the topological structure of the ἐμπειρία (empeiría) — the field of experience as it actually stands. The QQP is not a memory trace: it is an active node in the living network of the qualitative field, continuously resonating with all other QQPs through their qualitative connections. |
The QQP concept resolves a problem that has plagued discussions of qualia: the question of persistence. Are qualia momentary, disappearing when the experience ends? Or do they persist? The SUM answer is precise: the quale itself is momentary — the what-it-is-like-ness of this encounter at this moment. But the QQP it deposits persists in the topological field M₄, actively connected to all prior QQPs, available for resonance with future encounters. The red of the tomato in this moment will not persist as a quale — the moment passes. But its QQP will persist in the field, ready to resonate with the next encounter with that shade of red, with tomatoes, with summer kitchens, with everything qualitatively connected to it in the network of the ἐμπειρία.
Qualia — The Crystallized Qualitative Field
| Qualia (SUM definition — distinct from standard philosophical usage) | The complete package of qualitative information of the entire conscious field, crystallized in qualitative time (τ). Qualia is not the simple plural of quale (multiple instances of single qualities). It is the higher-order concept: the crystallization of the entire M₄ field in the living present — all qualia active simultaneously, their resonances and GRAVIS shaping the full qualitative reality of this moment. Qualia is what the field is doing right now, as a whole. It includes not only the Consciente register (witnessed qualia) but the Subconsciente register (active, unwitnessed qualitative mass) and the Inconsciente stratum (pre-personal qualitative ground). Qualia is the full chord; quale is a single note. |
The distinction between Quale and Qualia is one of the most original contributions the SUM makes to the philosophy of mind. In standard philosophical usage, ‘qualia’ is simply the plural of ‘quale’ — multiple qualitative properties. The SUM proposes a different and more precise relationship: Quale is the singular qualitative information of a specific encounter; Qualia is the crystallized totality of the qualitative field in qualitative time. Qualia is not many qualia added together. It is what the field is doing all at once, in all its registers, in the living present.
Gethsemane as Qualia: not only the qualitative character of the night air, or the olive trees, or the sound of voices, or the taste of fear — each of these is a quale. Qualia is what all of these together crystallize in the living present of consciousness: the full qualitative reality of that moment as it is experienced from the inside, in all its dimensions simultaneously. It is not a memory: it is experience. The experience of flying in a dream, the experience of witnessing a transformation, the experience of a crisis of conscience — these are Qualia: the crystallization of the entire qualitative field in qualitative time.
“The stream of consciousness is not one thing after another. It is everything at once, filtered and structured by the selective attention of consciousness, but present in its fullness to the whole of experience simultaneously.”
— William James, The Principles of Psychology, 1890
James describes Qualia without having the word for it: the fullness of the stream at any moment, containing more than attention can hold, structured by the lived body and the history of the field. Qualia is the name for that fullness: the crystallized qualitative field as it stands in the living moment, real in all three registers (Consciente, Subconsciente, Inconsciente), shaped by all the QQPs the field has accumulated, and oriented by the GRAVIS that weights each region of the topological network.
The Three-Register Structure of Qualia
The SUM’s most precise contribution to the account of Qualia is the three-register structure of the qualitative field. Standard philosophy of mind considers only the phenomenal quality of conscious (Consciente) experience. The SUM extends this: the full Qualia of a moment includes the qualitative activity of all three registers simultaneously.
In the Consciente register: the qualia that the Witness is actively holding — the witnessed qualitative content, the □T(q) events. These are what standard philosophy calls phenomenal consciousness. In the Subconsciente register: the qualitative content that is operationally active but not currently held by the Witness — the ◇T(q) events. These have full qualitative reality: the Subconsciente is not the absence of qualia but their presence without the Witness relation. The Existential Mood Foam — the ambient qualitative background that colors all experience before any specific content enters the Witness — is Subconsciente Qualia. In the Inconsciente register: the pre-personal qualitative ground, the GRAVIS deposited before the Witness existed. This too has qualitative reality — it is the oldest and heaviest layer of the qualitative field, shaping everything that grows above it.
Qualia(t) = ΨΝ[□T(q) + ◇T(q) + T₀(q)] The total crystallized qualitative field: Consciente + Subconsciente + Inconsciente in qualitative time τ
This formulation resolves the long-standing debate between access consciousness and phenomenal consciousness. Access consciousness (Ned Block’s term) corresponds to the Consciente register: what the Witness holds, what is available for report and reasoning. Phenomenal consciousness extends across all three registers: the qualitative field is fully real in the Subconsciente and Inconsciente, even where the Witness does not have access. Qualia, in the SUM’s sense, is larger than access consciousness — it is the full qualitative reality of the field at any moment, most of which the Witness has not met.
The Sensible Universe as the Field of Qualia
The name of the model — the Sensible Universe — is a direct statement about Qualia. The universe is sensible: it is a universe in which the qualitative field of experience is not an epiphenomenon or a secondary property but the primary reality from which all other descriptions are abstractions. The physical description of the world is a third-person account of the same reality that appears from the inside as Qualia. Neither account is more real than the other: they are two registers of the same field.
“The world is not what I think but what I live through. I am open to the world, I have no doubt that I am in communication with it, but I do not possess it; it is inexhaustible.”
— Maurice Merleau-Ponty, Phenomenology of Perception, 1945
Merleau-Ponty names the inexhaustibility of Qualia: the world as lived, as inhabited from the inside, always exceeds any description of it from the outside. The sensible universe is not a pale shadow of some more real world of particles and fields: it is the world as it genuinely is when encountered by a conscious being from the inside. Qualia is not the representation of the world: it is the world, crystallized in the living present of a consciousness that participates in it through Λω — the love-constant that keeps the field genuinely open to what exceeds it.
XII. Formal Lexicon Entries — SUM Definitions
| Quale | The particular, precise, and individual qualitative information of a specific encounter — the what-it-is-like-ness of this experience, irreducible to any other and irreducible to any physical or functional description. A quale is always singular: not the concept of red but the quale of this red; not the concept of pain but the quale of this pain at this moment. Each quale deposits a QQP (Quale Quality Pin) in the topological network of the M₄ field when it is witnessed (□T(q)). The quale of an unwitnessed Subconsciente event is real but lacks the relational dimension of being found by the Witness. |
| Qualia (SUM — distinct from standard philosophical usage) | The complete crystallized qualitative field in qualitative time (τ) — not the sum of individual qualia but their simultaneous active crystallization in the living present of consciousness. Qualia includes all three registers: the Conscious (witnessed qualia, □T(q)), the Subconscious (operationally active unwitnessed qualitative mass, ◇T(q)), and the Unconscious (pre-personal qualitative ground). Qualia is the full chord; quale is a single note. To experience a place is not to experience a list of qualia sequentially: it is for Qualia to crystallize — all registers simultaneously — in the living present of a consciousness that is there. |
| QQP — Quale Quality Pin | The topological marker deposited in the M₄ field by a witnessed quale — the precise, non-interchangeable impression of this specific encounter. Not a memory trace but an active node in the living qualitative network, continuously resonating with all other QQPs through their qualitative connections. The accumulated network of QQPs over a lifetime is the topological structure of the ἐμπειρία (empeiría): the shape the field has taken through genuine encounter with reality. The QQP is the SUM’s answer to the philosophical problem of quale persistence: the quale is momentary; the QQP is permanent. |
| Qualitative Time — τ (tau) | The temporal dimension proper to Qualia — distinct from clock time (t). Qualitative time is the living present in which Qualia crystallizes: thick, contextually saturated, carrying the resonance of what came before and the anticipation of what comes next. A Qualia event in qualitative time is not a point but a wave. The experience of flying in a dream and the experience of witnessing a transformation are events in qualitative time: they have duration, texture, and reality independent of their clock-time correlates. |
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Sources
Ancient and Early Modern
Aristotle. (c. 350 BCE / 1984). De Anima. Trans. J. Barnes. Princeton University Press.
Locke, J. (1690 / 1975). An Essay Concerning Human Understanding. Ed. P.H. Nidditch. Oxford University Press.
Berkeley, G. (1710 / 1998). A Treatise Concerning the Principles of Human Knowledge. Ed. J. Dancy. Oxford University Press.
Hume, D. (1739 / 2000). A Treatise of Human Nature. Ed. D. Norton & M. Norton. Oxford University Press.
Kant, I. (1781 / 1998). Critique of Pure Reason. Trans. P. Guyer & A. Wood. Cambridge University Press.
C.I. Lewis and Logical Empiricism
Lewis, C.I. (1929). Mind and the World-Order. Charles Scribner’s Sons.
Sellars, W. (1956). Empiricism and the Philosophy of Mind. In: Minnesota Studies in the Philosophy of Science, Vol. I. University of Minnesota Press.
The Canonical Papers
Nagel, T. (1974). What Is It Like to Be a Bat? The Philosophical Review, 83(4), 435–450.
Jackson, F. (1982). Epiphenomenal Qualia. The Philosophical Quarterly, 32(127), 127–136.
Jackson, F. (1986). What Mary Didn’t Know. Journal of Philosophy, 83(5), 291–295.
Levine, J. (1983). Materialism and Qualia: The Explanatory Gap. Pacific Philosophical Quarterly, 64, 354–361.
Block, N. (1995). On a Confusion About a Function of Consciousness. Behavioral and Brain Sciences, 18(2), 227–247.
Chalmers, D. J. (1995). Facing Up to the Problem of Consciousness. Journal of Consciousness Studies, 2(3), 200–219.
Chalmers, D. J. (1996). The Conscious Mind: In Search of a Fundamental Theory. Oxford University Press.
Dennett, D. (1988). Quining Qualia. In: A.J. Marcel & E. Bisiach (Eds.), Consciousness in Contemporary Science. Oxford University Press.
Dennett, D. (1991). Consciousness Explained. Little, Brown and Company.
Neuroscience
Crick, F. & Koch, C. (1990). Towards a Neurobiological Theory of Consciousness. Seminars in the Neurosciences, 2, 263–275.
Tononi, G. (2004). An Information Integration Theory of Consciousness. BMC Neuroscience, 5, 42.
Tononi, G. & Koch, C. (2015). Consciousness: Here, There and Everywhere? Philosophical Transactions of the Royal Society B, 370.
Friston, K. (2010). The Free-Energy Principle: A Unified Brain Theory? Nature Reviews Neuroscience, 11, 127–138.
Damasio, A. (1999). The Feeling of What Happens: Body and Emotion in the Making of Consciousness. Harcourt.
Phenomenology
Husserl, E. (1913 / 1982). Ideas I. Trans. F. Kersten. Kluwer.
Husserl, E. (1928 / 1966). The Phenomenology of Internal Time-Consciousness. Trans. J. Churchill. Indiana University Press.
Merleau-Ponty, M. (1945 / 2002). Phenomenology of Perception. Trans. C. Smith. Routledge.
Heidegger, M. (1927 / 1962). Being and Time. Trans. J. Macquarrie & E. Robinson. Harper & Row.
James, W. (1890). The Principles of Psychology. Henry Holt and Company.
Contemporary Philosophy of Mind
Levine, J. (2001). Purple Haze: The Puzzle of Consciousness. Oxford University Press.
Chalmers, D. J. (2010). The Character of Consciousness. Oxford University Press.
Goff, P. (2019). Galileo’s Error: Foundations for a New Science of Mind. Pantheon.
Noe, A. (2004). Action in Perception. MIT Press.
Zahavi, D. (2005). Subjectivity and Selfhood: Investigating the First-Person Perspective. MIT Press.
Sensible Universe 