or those of you who *want* practice with Scheme, go with The Little Schemer.
* *The Haskell Road to Logic, Maths and Programming*, by Kees Doets and Jan van Eijck, currently $22 on [Amazon](http://www.amazon.com/dp/0954300696) is a textbook teaching the parts of math and logic we cover in the first few weeks of Logic for Philosophers. (Notions like validity, proof theory for predicate logic, sets, sequences, relations, functions, inductive proofs and recursive definitions, and so on.) The math here should be accessible and familiar to all of you. What is novel about this book is that it integrates the exposition of these notions with a training in (part of) Haskell. It only covers the rudiments of Haskell's type system, and doesn't cover monads; but if you wanted to review this material and become comfortable with core pieces of Haskell in the process, this could be a good read.
+(The book also seems to be available online [here](http://fldit-www.cs.uni-dortmund.de/~peter/PS07/HR.pdf).)
The rest of these are a bit more advanced, and are also looser suggestions: