G'day all. Quoting David Menendez <d...@zednenem.com>:
Are there any instances of Boolean that aren't isomorphic to Bool?
Sure. Two obvious examples: - The lattice of subsets of a "universe" set, where "or" is union "and" is intersection and "not" is complement with respect to the universe. - Many-valued logic systems. - Intuitionistic logic systems. - The "truth values" of an arbitrary topos (i.e. the points of the subobject classifier). Look up "Heyting algebra" for examples. Cheers, Andrew Bromage _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe