Found in 2 comments on Hacker News
This book like no other just makes me smile. I read this right after I graduated and started my "real" learning in programming and math. The intermission page list books on logic and set theory.

FYI: it is the first book in a "trilogy" -- but your next book could be either of the other two (their only prereq is The Little Schemer). Listed below:

Reasoned Schemer: http://www.amazon.com/Reasoned-Schemer-Daniel-P-Friedman/dp/... Seasoned Schemer: http://www.amazon.com/Seasoned-Schemer-Daniel-P-Friedman/dp/...

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