
I don't see any recommendations for Smullyan yet. The Lady or the Tiger is the classic I think, but I really loved Forever Undecided.
Anyway, Smullyan's book is a real treat. In the later chapters he even goes beyond Gödel. I've never completely figured out how much of that is Smullyan and how much is other published research.
What Gödel tells us is that, as long as you have a sufficiently powerful formal system, you cannot prove the consistency of the system itself. Modal logics are no exception.
If you are a computationalist (that is to say, you believe that the human mind can be emulated by a Turing machine), then you might want to take a look at Gödel, Escher, Bach, where Hofstadter discusses how the second incompleteness theorem applies to Turing machines.
You might also enjoy "Forever Undecided" by Smullyan. It uses puzzles to guide you to an intuition about what the incompleteness theorems means to human knowledge and its limitations. In the worst case it's a fun read.
Peace!
Managing the Professional Service Firm by David Maister. I can't keep this one on my shelf because I keep giving it away.
Cryptography Engineering by Bruce Schneier. Very accessible. Probably not very practical if you're not building a cryptosystem, but it's a nice way to get a lay understanding---and scare you enough about how many pitfalls there are. When you finish read this loving criticism also: http://sockpuppet.org/blog/2013/07/22/applied-practical-cryp...
Forever Undecided by Raymond Smullyan. Fun "puzzle guide to Gödel". Out of print but Amazon has used copies.
Quantum Computing since Democritus by Scott Aaronson. Fun survey but requires some familiarity with P/NP, quantum mechanics, linear algebra.
Programmers at Work by Susan Lammers. Interviews with computer pioneers. Interesting to see how they think and what they have in common.
Time Management for System Administrators by Thomas Limoncelli. Short, easy read with lots of practical advice for all of us.
The Mac is Not a Typewriter by Robin Williams. Very slim. Learn the difference between hyphens, en-dashes, and em-dashes.
If you do product design you might enjoy a slow musing read through Apple's original Human Interface Guidelines.
Those last three combined probably weigh half of the Tufte book.
Have a nice vacation! :-)
Some other nice resources on Godel are:
- Gödel's Proof by Nagel and Newman
- Forever Undecided by Smullyan