Illusionism is a branch of materialism which argues that phenomenal properties of consciousness aren't ontologically subjective. Illusion is that we tend to think it is, hence the name. Ontologically, consciousness is actually objective, can be completely known through the third person.

This isn't to say that consciousness doesn't exist or that it doesn't have a subjective character, but just that all its properties can be completely described and accessed objectively.

Parallel can be drawn with Dennett's response to the knowledge argument, Dennett argues that Mary having learned everything physical about the experience of colour (physics, physiology, deep knowledge about how and why neurology allows experience of colours etc.) already experienced them in the black and white world. She's done it through objective route, by learning everything physical relevant to the experience rather than experiencing it subjectively (interaction of light with her body).

I agree with Dennett that qualia doesn't have 3I-P properties non-materialists argue it has. His paper, 'Quining Qualia' makes a convincing case. There is nothing private or exclusively subjective about consciousness. Therefore, qualia isn't a good criticism of materialism.

However, in some talk given by him, he gave an example of red stripes on the American flag and argued that red stripes don't exist, they only seem to. There are no red stripes on the screen (in the objective world) nor on your retina nor in the brain.

This brings me to the confusion since I understood illusionism to deny that consciousness is something inaccessible from the third person, objectively, not that it doesn't exist at all.

I think it's true that redness can't be found neither in objective world nor in the brain which makes me confused. Redness is physical and therefore exists, but if it does, where is it? Every physical thing has a location in space and time.

If we conclude there is no redness at all, that it's some kind of illusion (whatever its nature), than what are my eyes and brain seeing? What is the secret of magician's trick Dennett is trying to explain?

  • Some of this is a bit hard to follow, at least for me. Specifically, you seem to use a lot of double or triple negatives (e.g. "since I understood illusionism to deny not that redness isn't there at all") Its hard for me to parse what you mean by that (maybe its just me?).
    – JMac
    Apr 23 at 17:00
  • @JMac Sorry about that. Here is some clarification: This brings me to the confusion since I understood illusionism to deny that consciousness is something inaccessible from the third person, objectively, not that it doesn't exist at all. Apr 23 at 17:11
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    Isn't the difference purely terminological? "Consciousness", as we normally think of it, with only privately accessible phenomenal properties, does not exist, what does exist is something else that creates the above impression, hence "illusion". It is the same with rainbows. They do not exist as solid objects in the sky one might naively take them for, what does exist is something else, an optical effect.
    – Conifold
    Apr 23 at 18:01
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    Rainbows do not exist, what we are experiencing is a play of light on water drops. Or they do exist as an optical effect. I do not see any problem with saying either, it is a purely verbal issue with the word "exist". As used colloquially, it is vague, ambiguous and ill-defined, so there is no point fussing much over it. The 'paradox' goes away once we rephrase what expressions with "exist" are intended to mean in more precise terms.
    – Conifold
    Apr 23 at 19:24
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    Rainbows are refraction of light as it passess between air and water drops. That play of light and water drops is exactly what rainbow is. Therefore, rainbows are a physical phenomenon and exist. They have a location in space and time because water droplets, light and air have it. We experience visible light as colours and I'm not sure where do these colours exist. You can't find them in the brain nor the outer world. Apr 24 at 9:54

1 Answer 1


"Illusionism" as an "-ism" should be handled, like all other "-isms", with protective gloves and/or bargepole.

TL;DR: The experience of redness does exist, or at least it does for those of us not afflicted with some physiological impairment of the retinas or (ventro-medial?) occipital cortex or the like. The experience is intrinsically subjective and amounts to more than everything which can be written down about it by someone attempting an exhaustive objective description.

I would have thought that the occurrence of events are part of the set of things which we can be reasonably certain about. Yes I know, we can be mistaken, misled even, about many of our subjective experiences but it is not reasonable to assert that all experience is illusion. That is about the same as asserting that nothing is true; both statements contain a form of self-contradiction.

A much better way of describing our subjective experiences is that they are constructions created by and within one's own brain. Certainly this is what modern neuroscience is telling us about the matter. The mainstream philosophical way of referring to this is: "what it is like to be" -something or other - which is the embodiment of the experience. (See Thomas Nagle What is it like to be a bat? in his book Mortal Questions.)

<Redness is physical...... but where is it?> Yes the redness, or any other sensory awareness for that matter, is embodied in a physical process within the brain. Steven Lehar describes our qualia as data structures and IMO this must be correct (see: http://slehar.com/wwwRel/Lehar.html?fbclid=IwAR18R5s4FPELPhKuDLvVeWN3VkbHJ4192ceeNr-Trd6iWlzW6CqBK_WDHQ8) In other words our brains are creating and maintaining data structures which are about, ie represent, everything we come across in the world around us and about each of us ourselves.

The most succinct description of what is going on which amounts to the "something it is like something to be it" is: the model of self in the world. This is a central reference process (or device if you like) which serves as the vitally important "You are Here!" indicator which is essential for us to be able to navigate through our physical and social environments. This idea is not new; it has been put forward by many people. The two people I most gained apprecialtion of it from are Susan Blackmore an English psychologist and Thomas Metzinger a philosopher.

In fact our consciousness (C), which I think we should define as rememberable awareness, is more exactly the process of updating of the model of self in the world. This is so because the MSITW is a set of assertions and predictions about what is around us and what we are and what we are doing which of course are all based on memory. To the extent that the model correctly predicts what is happening, there is not need for much feedback of this and they do not form part of C of the moment. What is vitally important rather is everything about the situation which was not correctly predicted.

Every discrepancy is assessed promptly (ie very fast) by the CNS areas which mediate detection and responses to archetypal dangers and threats, and to potential life enhancing resources. We experience these assessments as emotions. More detailed, complex, and abstract detections and recognitions occur within the cortex and take longer to process. The emotional charge attached to such novelties of the environment or self forms a critical part of the memory of each thing or event and are a fundamental source of meaning.

So it is that redness, or any other quale you wish to focus on, is embodied in patterns of neuronal activity and they are part of C of the moment to the extent that they form part of the MSITW. They exist explicitly whilst the neuronal interaction patterns which embody them are active. They exist implicitly, when not active, in the form of all the changes which have occurred to each and all of the neurons involved in the particular interaction patterns as a result of being part of each respective pattern.

  • Freud describes memory as capacity and function of the biological ego. The ego, the biological effort to govern action in the sensory context, forms and incorporates the memories of its interactions with other humans and the non-human world. Most of the memories are unconscious at any moment. So I do not walk around knowing whether or not I can play the piano. But if someone asks me, "Do you play the piano?" I take inventory of my memories of self and respond, "No." The old joke, "Can you play the piano?" "I don't know! I never tried!" Knowledge of materialism and rainbows are ego-memories. Apr 24 at 19:33
  • @MarkPeaty The thing which doesn't make sense to me is that Dennett claims to be a reductionist while he says that redness can't be found in the brain. This seem to be contradictory. Reductionism implies redness is physical and therefore it must exist somewhere in time and space. I personally fail in grasping where that might be. To say it's not there at all, also doesn't make sense to me. I'm not sure what am I missing. Apr 26 at 13:17
  • @DarioMiric I agree. Of Dennett's writings I read Consciousness Explained many years ago and very much liked his person-as-virtual-machine idea, but I found other things to be very laboured. As for the quale of redness....it must be in the brain IMO; where else could it be? As far as I am concerned, all qualia, indeed all mental objects, are dynamic logical structures (DLS) within the brain which are about things outside the brain. (Occam's razor cuts to the quick of this IMO.)
    – Mark Peaty
    Apr 27 at 16:11

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