# What are good elementary examples for teaching/introducing/learning about Intuitionistic Logic or Heyting Algebras?

For example, I have heard of a topological one wherein negation means the interior of the complement (but still would like a reference).

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The wikipedia entry for intuitionistic logic en.wikipedia.org/wiki/Intuitionistic_logic gives some references and in particular has a little bit to say about the topological interpretation you aluded to. See the section "Heyting Algebra Semantics". –  Adrián Barquero Oct 22 '10 at 16:51

An excellent book is also http://www.amazon.com/Lectures-Curry-Howard-Isomorphism-Foundations-Mathematics/dp/0444520775. This book is more focused on the $\lambda$-Calculus but it has some really excellent sections on general intuitionist logic, including Heyting Algebras, Hilbert Proofs, the (Gentzen's) sequent calculus and things like that.