The proper title of Hofstadter's book is
Godel, Escher, Bach: An Eternal Golden Braid. It belongs in Philosophy of Science, along with Edmund O. Wilson's
Consilience. He coined the word.
I too would vote for
The Meme Machine by Susan Blackmore. Cognitive Science, I think.
Complexity: The Emerging Science at the Edge of Order and Chaos by M. Mitchell Waldrop for the Math section.
And I'd concur that Gleick's
Chaos goes on the list.
For the Biology section,
At Home In the Universe by Stuart Kauffman
The Lives of a Cell, by Lewis Thomas
For the History of Science section,
The Dream Machine, another good Waldrop book (and how I came upon his
Complexity).
The History of Physics, by Isaac Asimov. The Good Doctor leads us from the Greeks to the neutrino. This comprises the original three-volume set,
Understanding Physics, comprised of
Motion, Sound, and Heat,
Light, Magnetism, and Electricity, and
The Electron, Proton, and Neutron, as well as including additional material abstracted and rewritten from
The Neutrino. You'll know your way around the major branches of physics fairly well, and also around the history of the title.
For the Physics section,
The Force of Symmetry, the best relatively non-technical treatment of the current physical understanding of force and matter that I have seen. Absolutely the best explanation of the Laws of Spin and Statistics for bosons and fermions I have ever seen. A watershed book for me.
I too liked
Six Easy Pieces, but I think that
QED: The Strange Theory of Light and Matter is more than worthwhile.
The Feynman Lectures on Physics, known to a couple generations of physics majors as "The Red Books," probably should go on the list, but with a note that they are not for beginners. This is the real deal, and you'll know a fair bit about how physicists use calculus when you're done. You should have been exposed to calculus enough that you won't get lost, though it's probably not necessary to have taken a class in the immediate past.
I concur with the recommendation of both of Brian Greene's books. I also like Penrose's
The Road to Reality, but agree that it is a very tough read.
I very much liked Heinz Pagels'
Perfect Symmetry. It is an excellent lead-in to
The Elegant Universe; gives you an idea of the intellectual climate into which string theory dropped.
No physics bookshelf could possibly be complete without The Black Book:
Gravitation. The definitive tome, by three of the masters of the field: Kip Thorne (he of the infamous bet with Hawking), John Archibald Wheeler, and Charles Misner. EXTREMELY difficult. You will not get through this book without a good understanding of calculus. This is college curriculum, and not for freshmen.
And an oldie but a goodie:
Relativity, by the master himself: Albert explains his theory for the sophisticated intellectual (though not necessarily the physics major). Highly accessible, and the best possible introduction to the theory, by the man who invented it.
That'll do to go on with. Having just moved, and facing the prospect of another move in the not-too-distant future, though not nearly so far, I have absolutely no intention of unpacking about 40 boxes of books until the situation clarifies itself, or we are done moving.