Qualia are internal variables but they are taken from different realm
Consider a simple example: E = mc². The law describes a relation between mass and energy, but notice that "E" isn't a physical object. It's a letter of the Latin alphabet, as are the other symbols in the equation. The Latin alphabet emerged at a particular moment in human history and reflects the features of human language (which decomposes into roughly thirty sounds), as well as the physical conditions of writing. Different alphabets evolved alongside different instruments and surfaces: cuneiform, for instance, was shaped by the practice of pressing a stick into wet clay.
If an alien were handed a book of mathematical equations, it could learn a surprising amount about human language and the materiality of human writing. The letters play a functional role inside the equations, but they're imported from somewhere else entirely.
In this post I want to suggest that qualia work the same way: they are objects from a different realm, conscripted by the human mind to serve as internal variables.
The "internal variable" part is the easier half. The feeling of red is needed to designate red objects in the world. We can't use red itself for that – red is just a wave frequency, and the brain has no way to process a frequency directly. In the same way, we can't use energy itself as the symbol for energy in Einstein's equation. We need to borrow from another realm, one that contains objects fit to serve as symbols. Mathematics borrows from written language.
What I'm suggesting is that qualia are borrowed objects too. This doesn't dissolve the hard problem - we still don't know what the realm of qualia actually is - but we can develop some intuitions about its properties by pushing the comparison with letters as far as it will go.
What the analogy gets us
1. The inverted spectrum is fine. If colorblindness involved a complete and consistent recoding of qualia, the system would still work – just as E = mc² remains functionally identical if we rewrite it as L = ub².
2. The set is finite but large. Humans have created a finite number of letters, though the count grows enormous once you include hieroglyphs and pictograms.
3. They come pre-structured for use. Letters were shaped to be easily combined and communicated. This doesn't require intelligence – DNA codons are also a kind of "letter," produced by evolution rather than design.
Where the analogy breaks
Qualia depend only on themselves, whereas letters can be built from simpler parts (dots, strokes, curves). And we can't easily create new qualia – perhaps only under strong psychedelics or direct brain stimulation.
A pet theory
My pet theory is that qualia are a special kind of mathematical object - one that depends only on itself. Because of this, no explanation can reach them. If something depends only on itself in order to exist, no further explanation of its existence is needed or even possible. But qualia also have a structural interface with the world, and that's what lets them function as symbols.
The knowledge argument, briefly
This view fits the knowledge argument neatly. We can know that we have functional qualia, but we can't describe their qualitative side - just as the relation between mass and energy is real but can't "know" which letters we happened to use to write it down.
Discuss