What is it like to be China? How different from that would it feel to be the United States? - Douglas Hofstadter

Saying that studying the brain is limited to the study of physical entities would be like saying that literary criticism must focus on paper and bookbinding, ink and its chemistry, page sizes and margin widths, typefaces and paragraph lengths, and so forth.

Think of a dentist who has a list of
patients, and for each patient, a list of teeth. It makes perfect sense (and
plenty of money) to hold the patient fixed and vary his teeth-but it makes
no sense at all to hold one tooth fixed and vary the patient. (Although
sometimes it makes good sense to vary the dentist ... )

"In the thirty-first year, however, Godel published his paper, which in some ways utterly demolished Hilbert's program. This paper revealed not only that there were irreparable "holes" in the axiomatic system proposed by Russell and Whitehead, but more generally, that no axiomatic system whatsoever could produce all number-theoretical truths, unless it were an inconsistent system! And finally, the hope of proving the consistency of a system such as that presented in P.M. was shown to be vain: if such a proof could be found using only methods inside P.M., then — and this is one of the most mystifying consequences of Godel's work — P.M. itself would be inconsistent!"