I think unless you take a very linguistics heavy understanding of the emergence of qualia, you are over-weighting your arguments around being able to communicate with an agent being highly related to how likely they are to have consciousness.
In short, there are some neural circuits in our brains that run qualia. These circuits have inputs and outputs: signals get into our brains, get processed, and then, in some form, get inputted into these circuits. These circuits also have outputs: we can talk about our experience, and the way we talk about it corresponds to how we actually feel.
And:
It is valid to infer that, likely, qualia has been beneficial in human evolution, or it is a side effect of something that has been beneficial in human evolution.
I think both of the above statements are very likely true. From that, it is hard to say that a chimpanzee likely to lack those same circuits. Neither our mental circuits nor our ancestral environments are that different. Similarly, it is hard to say “OK, this is what a lemur is missing, as compared to a chimpanzee”.
I agree that as you go down the list of potentially conscious entities (e.g. Humans → Chimpanzees → Lemurs → Rats → Bees → Worms → Bacteria → Virus → Balloon) it gets less likely that each has qualia, but I am very hesitant to put anything like an order of magnitude jump at each level.
I think unless you take a very linguistics heavy understanding of the emergence of qualia, you are over-weighting your arguments around being able to communicate with an agent being highly related to how likely they are to have consciousness.
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You say:
And:
I think both of the above statements are very likely true. From that, it is hard to say that a chimpanzee likely to lack those same circuits. Neither our mental circuits nor our ancestral environments are that different. Similarly, it is hard to say “OK, this is what a lemur is missing, as compared to a chimpanzee”.
I agree that as you go down the list of potentially conscious entities (e.g. Humans → Chimpanzees → Lemurs → Rats → Bees → Worms → Bacteria → Virus → Balloon) it gets less likely that each has qualia, but I am very hesitant to put anything like an order of magnitude jump at each level.