Neural Substitution Fallacy

Representational Qualia Theory argues that consciousness consists of subjective qualities like redness and greenness. This means that consciousness depends on these qualities; it serves as a detector for them. Therefore, the idea of a neuro substitution doesn’t make sense. For instance, if redness changes to something that is no longer redness, the system must register this change. If whatever supports this quality changes to something that isn’t redness, the system is not functioning correctly if it does not report this change. As such, since its function is to detect qualities, consciousness is by definition substrate dependent on the qualities of subjecdtive experience.

How will the neuro substitution fail?

Two minimum requirements must be met for a system to be phenomenally conscious:

Something must be responsible for each elemental quality, such as redness or greenness.
There must be a mechanism to subjectively bind two or more qualities into a single subjective experience.

A simple theoretical example of this could be:

Specific neurotransmitters responsible for qualities, such as glutamate representing redness and glycine representing greenness.
At least one neuron that can perform the computational binding of these qualities.

Suppose we discover one neuron (or more) in the brain that is responsible for a particular voxel of visual perception. This neuron can fire either glutamate (representing redness) or glycine (representing greenness) to satisfy the first requirement. For the second requirement, we find one or more neurons that are responsible for subjectively binding that voxel of knowledge to the other voxels of visual perception.

Now, let’s consider a neuro substitution. When we reach the point of needing to neuro substitute the first pixel firing with either glutamate (redness) or glycine (greenness), our prediction is that only glutamate will produce a subjective experience of redness that can be bound into the overall subjective experience. This is where the substitution will fail, as no substitution will lead to a subjective experience of redness that can seamlessly integrate with the rest of the subjective visual experience.

The neuro substitution argument fundamentally overlooks the importance of qualities in consciousness. It begins by ignoring that one of the roles of consciousness is to detect and report on changes to qualities. It then performs a sleight of hand: when a quality is substituted with something different, it also replaces the detector of that quality, creating the illusion that the quality hasn’t changed, even though it has. This gives the false impression that the system is substrate independent. In reality, that is how abstract systems are designed to function. It doesn’t matter what quality or property represents abstract information, as long as one adjusts the terms appropriately to ensure that the same abstract information is preserved, even when it is represented by different properties.