In an interesting twist, in chapter 22 Hofstadter reveals that David Chalmers was a doctoral student of his. It so happens that Chalmers has made a career out of taking positions opposed to that of his former advisor. Chalmers is a champion of philosophical zombie thought experiments. Chalmers lectures on the notion that an unconscious copy of each of us is conceivable: it may take an alternate universe, but it is conceivable. As a result, there is a gap between the physical and mental. Hofstadter does a lot of poking good-natured fun at his former student, but he never adduces a single argument of any power.
In the end, I am a strange loop, as interesting a read as it has been, has not convinced me ot any of Hofstadter's distinctive positions; I have to say I agree more with John Searle. In the end, and here I disagree with John Searle, I am pessimistic we will be able understand consciousness beyond the level of correlation with physical substrates; I suspect it is a limitation of our condition.