I guess I'm not entirely sure what you mean by "understanding" and "predicting". As I said, if we could scan the bat's brain and figure out how all of its subsystems influence each other, we would know with a very high degree of certainty what happens to it when the bat receives a sonar signal. We could identify the changes in the bat's model of the world that would result from the sonar signal, and we could predict them ahead of time.
Thus, for example, we could say, "if the bat is in mid-flight, and hungry, and detects its sonar reflecting from a small object A of size B and shape C etc., then it would alter its model of the world to include a probable moth at the object's approximate location (*). It would then alter course to intercept the moth, by sending out signals to its wing muscles as follows: blah blah".
Are predictions of this sort insufficient ? If so, what additional predictions could be made by those other explanations you mentioned ?
(*) Disclaimer: I don't really know much about the hunting habits of real-life bats.
Are predictions of this sort insufficient ?
More irrelevant. None of them are actualy about qualia, about how things seem to experiencing subjects. You have Substituted an Easier Problem.
[Cross-posted.]
1. Defining the problem: The inverted spectrum
A. Attempted solutions to the inverted spectrum.
B. The “substitution bias” of solving the “easy problem of consciousness” instead of the “hard problem.”
2. The false intuition of direct awareness
A. Our sense that the existence of raw experience is self-evident doesn’t show that it is true.
B. Experience can’t reveal the error in the intuition that raw experience exists.
C. We can’t capture the ineffable core of raw experience with language because there’s really nothing there.
D. We believe raw experience exists without detecting it.
3. The conceptual economy of qualia nihilism pays off in philosophical progress
4. Relying on the brute force of an intuition is rationally specious.
Against these considerations, the only argument for retaining raw experience in our ontology is the sheer strength of everyone’s belief in its existence. How much weight should we attach to a strong belief whose validity we can't check? None. Beliefs ordinarily earn a presumption of truth from the absence of empirical challenge, but when empirical challenge is impossible in principle, the belief deserves no confidence.