If "inner experience" is equivalent to "consciousness" then indeed that is what we are discussing. I certainly don't know if that is the case. I used the term "sensation" as a subjective term specific to the capability of a given organism, it seems obvious to me that both a human and a bee have "sensation" when perceiving color. I think its pointless to explain that bee's "sensation" of color is a lot more crude that that of a human but thats, like I said before - irrelevant.
You seem to be using human consciousness as a reference point for judging the perception of other animals, for me this stance is just wrong. In your post #38 you attempt to prove (please tell me what you are actually trying to prove) that because humans have no ability to sense oxygen levels in their blood that somehow correlates to this discussion about color perception. I'm not sure what you want me to concede, please enlighten me.
I think it might help to dial the discussion down a level and build up from there, because animals are always going to be a philosophically fuzzy subject when discussing internal experience.
So let's look at a camera instead. Digital cameras include a light-sensitive sensor. It can detect color. Putting aside more modern ones that have facial recognition and whatnot for a moment and just going with an older basic model, there is no real processing of the content of the image. It is very basic input-output, action-reaction stuff.
Does such a camera have an internal experience of what it "sees"? I think that the straightforward answer is likely "no." If it did, it would mean that pretty much every chemical, physical or quantum interaction would generate an internal experience in something. Based on the demonstrated importance our nervous system and brain play in our own internal experience of the world, I feel safe in saying that this is not the case, or at the very least that if some internal sensation exists in all things in the universe, it is of a completely different kind and with a different basic mechanism than our own.
So then an internal experience is not merely the result of perception of a stimulus, but is the result of the brain processing that perception and constructing a mental model of the world based on the information that stimulus provides (in conjunction with all of the other stimuli being received). This is why, for instance, color perception varies significantly based on context and you can get things like the black-blue/white-gold dress.
The qualia are not faithful representations of what is detected by the eye, but generated by the brain as part of its modeling process. Different people may receive the same input and have very different internal experiences based on how the brain winds up collating all of the information and building its model.
Because of this, I consider it probable that most organisms with a complex central nervous system have some kind of internal experience of their senses with the odds of this more or less increasing with the complexity of their interactions with the world.
I think it is likely, for instance, that anything capable of displaying problem-solving skills when faced with a novel problem, especially when any degree of tool use is involved, most likely has the ability to do some level of predictive modeling in order to recognize what the likely results of different actions it can take will be. And I find it unlikely that anything would obtain the ability to model future states of a system without having a brain that maintains some degree of modeling of the active state of their environment based on sensory input.
If the internal model is the thing that provides us with qualia, then it seems reasonable that such creatures also have an internal experience. And I think at least the basic modeling of the environment spreads much father out in the animal kingdom than just the obvious tool-users and problem-solvers. Those are just the ones I'm most confident likely have an internal experience of their senses.
In general, I think it's likely that anything with seriously complex sensory input probably has an internal model of it. So single photo receptor that detects day/night cycles? That may just alter certain functions within the organism in response to amount of light received without any direct perception by the organism itself. The compound eye of an insect where the input from each sensor needs to be put together in order to facilitate object recognition for the detection of food, threats and family? I'm pretty sure that that requires a degree of internal modeling and thus, probably, qualia.
This is also the major reason why I'm curious as to whether some of our most advanced AIs have started having some degree of limited experience because they are essentially performing a degree of internal modeling on sensory input including that very same object recognition I was talking about.
Ultimately, though, we don't really fundamentally know where subjective experience comes from, and so everything and nothing having it is technically within the realm of possibility. In my more existentialist moments, I'm even open to the possibility that I don't have a subjective experience of anything either and that this is a delusion generated in my brain telling me that I have subjective experience. I could even quibble a bit with cogito ergo sum, although not very strenuously.
Anyway, there are no hard answers available as far as the internal experiences of others, including other species and even other objects, but I do think what indirect evidence we have points more or less in the direction outlined above.
Edited by Delta1212, 21 April 2017 - 05:53 PM.