Fairly often we hear philosophers explaining how it is that a scientific theory of consciousness is a goal that can never, in principle, be reached. Eric Schwitzgebel has his version (here). His has three simple steps:
(first) No general theory of consciousness can be justified except on the grounds that it gets it right about certain facts known independently of that theory. Those facts include facts about the presence or absence of conscious experience in a wide variety of actual and possible beings that are unlike us in potentially relevant respects — beings like frogs, insects, weird sea life, computers and robots of various types, alien beings of various types, and collective super-organisms of various types.
(second) Independently of a well-justified theory of consciousness, we cannot know, with regard to most such beings, whether consciousness is present or absent.
(third) Therefore, no general theory of consciousness can be justified.
This is not how scientific theories are created or accepted. There is no rule that says that a theory must be correct about facts that are independent of the theory. Plate tectonics did not need an independent test planet to be accepted; quantum mechanics did not need another universe. Scientists like a theory to be falsifiable, at least in principle, or to have a pretty high Baysian probability. But the real test is whether, taking everything together, the theory is convincing to the scientists in that area of research.
What happens is that a lot of facts and little local theories accumulate and then they collect into larger groups and with luck into one big theory. Thousands of experiments and observations pave the way. New ways and machines to observe are invented. In this process, the terms (the words) involved change their meanings, split in two, merge, become analogies of other terms in other theories. For it is not the words that are important; it is the physical reality that is important and the words are just tools to describe a particular model of reality. The sub-questions that seem to need answers appear and disappear as understanding increases. The arrogance of someone saying that no general theory of consciousness can be found and saying this before the science is more than out of the gate, is mind-boggling.
But then there are always people who would sooner play silly, entertaining word games, then have a deep understanding of something.