What does "inseparable" mean? That the sensation occurs at the same time that the neurons fire? That may be true, but it doesn't make them equivalent.
> It's like saying a flashlight that is on is different than photons traveling away from a light bulb with a battery and a current.
They're not the same, for what it's worth. The term "flashlight" conveys a certain intent and structure that "photons traveling away from a light bulb with a battery and a current" does not.
> The sensation of red is caused by and is only possible by neurons firing. The neurons firing causes and only results in the sensation of red. The observer does not know the difference.
The fact that two different phenomena are closely coupled via a cause and effect relationship does not make them the same phenomena.
If you push two magnets together, the fact that the same force causes them to attract or repel does not mean that the motion of the first is literally equivalent to the motion of the second, or that the force itself is literally equivalent to either motion. They are closely correlated, but ultimately distinct.
You just can't avoid the fact that qualitative phenomena do exist in their own right. They can't be explained away using a physical model that assumes from the get go that they don't exist.
Erwin Schrodinger said:
> Scientific theories serve to facilitate the survey of our observations and experimental findings. Every scientist knows how difficult it is to remember a moderately extended group of facts, before at least some primitive theoretical picture about them has been shaped. It is therefore small wonder, and by no means to be blamed on the authors of original papers or of text-books, that after a reasonably coherent theory has been formed, they do not describe the bare facts they have found or wish to convey to the reader, but clothe them in the terminology of that theory or theories. This procedure, while very useful for our remembering the facts in a well-ordered pattern, tends to obliterate the distinction between the actual observations and the theory arisen from them. And since the former always are of some sensual quality, theories are easily thought to account for sensual qualities; which, of course, they never do.