As I see it the subjective experience of redness, indeed any shade of any hue, any timbre of sound, any taste, any aroma, etc, is what it is like to be a particular current behaviour of a certain population of neurons within the brain. Such particular patterns of activity I call a dynamic logical structures (DLS).

In relation to the most recent update of the camp statement my point here is to emphasise that all such DLS are learned behaviours. As such I take it for granted that, because the learning has taken place within the one particular brain of an individual whose personal history is, ultimately, unique, there is no way that a DLS in that person's brain is going to be identical to a DLS in the brain of another person in the same situation at the same time and place. I fully agree that there will be - or at least ought to be -  very significant similarities because we are all members of the one species. There may also be quite significant differences for the same reason that we humans all have finger prints which are unique in their exact details but generally seem to manifest in patterns which can be conventionally  named. 

The reason for the similarities and differences is basically the same for brain structures as it is for fingerprints: there must be structures which effectively accomplish certain functions but the precise 'final' layout in each case it achieved through epigenetic adaptation to the particulars of the location and activities of the cells building the structures. In the case of fingerprints the need is to have skin on the fingertips which is robust and resistant to wear yet has good grip, and is prolifically endowed with contact sensory neurons. The evolved solution of our species has been to grow fingertip skin with lots of corrugations which maximise the surface area, underlaid with good quality connective tissue which holds the corrugations in place while allowing flexible adaptation to the shapes of things being touched. The genetic coding which produces this 

In analogous manner our brains have evolved topologies which reflect the need to systematically map the patterns of sensory inputs and to dynamically match up the inputs of different sensory channels so as to create sufficiently comprehensive and exact representations of objects and entities in the current environment. As well as this we have equally comprehensive output maps which create the patterns of muscle movements we need to respond to threats and/or resources currently important in our surroundings. 

Insofar as the purpose of brains is to make animals' muscles move in the right way at the right time we can reasonably assume that the subjectively experienced, non linguistic, description of the world of the members of any particular species is likely to be very similar because their neural architecture is the outcome of their species' history of natural selection. Us humans, by and large, should also have such basic similarities in our pre linguistic experience of the world. However, given that we have also evolved to live within, through, and by means of a linguistic description of ourselves and our world, it is open to speculate that the individual variability now embodied in the brains of all of us may include a much wider range than was present before our ancestors came to rely absolutely on tool using culture and language with versatile grammar. 

Xodarap, AKA Mark A Peaty