By Inside_my_head.jpg: Andrew Mason from London, UK derivative work: -- Jtneill - Talk (Inside_my_head.jpg) [CC BY 2.0 (], via Wikimedia Commons
Reading Time: 4 minutes By Inside_my_head.jpg: Andrew Mason from London, UK derivative work: -- Jtneill - Talk (Inside_my_head.jpg) [CC BY 2.0 (], via Wikimedia Commons
Reading Time: 4 minutes


Qualia – what are they?

Qualia (sing. quale) are subjective experiences, in simple terms. Whether it be looking and experience a colour, such as having the subjective experience of redness, or any other such experiential event. These are qualities of ‘phenomenal character’. There are other, more restrictive definitions which are worth looking into and can be found here, at the SEP. Accounting for qualia is known as the Hard Problem of Consciousness.

What do qualia entail? Well, as the SEP says:

The following would certainly be included on my own list. (1) Perceptual experiences, for example, experiences of the sort involved in seeing green, hearing loud trumpets, tasting liquorice, smelling the sea air, handling a piece of fur. (2) Bodily sensations, for example, feeling a twinge of pain, feeling an itch, feeling hungry, having a stomach ache, feeling hot, feeling dizzy. Think here also of experiences such as those present during orgasm or while running flat-out. (3) Felt reactions or passions or emotions, for example, feeling delight, lust, fear, love, feeling grief, jealousy, regret. (4) Felt moods, for example, feeling elated, depressed, calm, bored, tense, miserable.

Now here, feeling in a particular mood is not to say what those physiological mechanisms of a mood are (hormones, blood etc), but the experience of having them, the feeling. Some other philosophers include things like the experience of understanding a sentence or thinking.

 The question of importance is what are these qualia made of, if they exist (which is an important addendum)?

Brent Allsop recently commented on a previous article about qualia, here (“Philosophy 101: Qualia”):

At the close of your article on qualia, you say:

“The main point to take away, perhaps, is that there are theories of qualia which can fit and cohere with a naturalistic worldview. So worry not! Trying to get your head round them, well, that’s another story…”

We have a new theory that just might be a real “naturalist world view” (if science bears out the predictions being made). The prediction is that qualia are just physical qualities. The reason we can’t objectively detect them, is simply because our current observation techniques are done purely, abstractly, and hence we are qualia blind.

Here is a version of the paper, where we describe what qualia blindness is and what is required to not be qualia blind and “eff the ineffable”. We’ve already presented this material in multiple venues. We are preparing this version to present at the Long Island Philosophical Society next year where Danial Dennett will also likely be presenting.…

Would love to hear anyone’s thoughts on this. Daniel Dennett thinks that qualia are ineffable, and this is why he thinks qualia should be ignored or “quinned”. Do you think if we show how we might detect physical qualia, and hence eff the ineffable, we’ll be able to convert him to the camp that there is merit to the idea of qualia? I like to think we will be able to accomplish this.

The abstract for the paper is as follows:

Notice that the word “red” is not red.  To know what red means, you need to know how this abstract representation (red) is experienced as a redness quale. Your lens focuses 650 nm light onto your retina and sends it to be transformed into a set of physical qualities that is redness.  The same thing is true of all our abstract knowledge of the physics of the brain.  For example, we know almost everything about how the neurotransmitter glutamate behaves in a synapse, at least abstractly.  Perhaps it is glutamate, for example, that is redness. Then, to not be qualia blind, we need to know that we should be interpreting this abstract description of how glutamate (or other physical phenomena) reacts in a synapse as an abstract description of a redness physical quality.

To explain this, Allsop creates a simple model:

To keep things as simple as possible and to only focus on what is necessary to describe the qualitative method of effing the ineffable, imagine a universe with two colors; red and green.   There is no slightly different shade of red. No grey. No white. No smells or sounds. Just red and green, and an observer who experiences these two colors. The red and green can be described in terms of physical properties, such as wavelength, but the experience of redness and greenness may, for all we know, differ between two observers with brains that are identical except for an inverted perception system (Fig. 1). The physical properties of the surface of the strawberry (in that it reflects red light) are often mistaken for the physical properties of experience. But to the observer, the experience that is real is not the wavelength. The knowledge of redness and greenness is real. Now imagine that, in this simplified world, knowledge is composed of 2 elemental sets of physical qualities that exist in the brain. In this simplified world, glutamate reacting in a synapse, has the redness quality we experience as redness, and reacting glycine has the physical greenness quality. These compounds could be observed and measured in the brain, and if so, then we could observe inverted qualia, or the phenomenon that two inverted brains produce different qualia in response to the same external stimulus. One experiences redness, the other, greenness.These are testable claims.

I wonder whether this sort of approach just sort of moves the hard problem one level back. For me, all experiences and mental phenomena at the very least supervene on the physical, irrespective of what mental phenomena actually are. Indeed, it’s almost immaterial (pun entirely intended) what mental phenomena ontologically are given this supervenience.

In other words, if I understand the paper correctly, it is moving the hard problem of consciousness from the instantation of redness in the strawberry from the strawberry to the experience felt, now from the brain chemical to the experience felt.

I could be wrong, however…

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Jonathan MS Pearce

A TIPPLING PHILOSOPHER Jonathan MS Pearce is a philosopher, author, columnist, and public speaker with an interest in writing about almost anything, from skepticism to science, politics, and morality,...