abstract algebra algebra algebraic structure antisymmetric relation asymmetric relation automorphism bertrand russell bijection binary operation binary relation category theory codomain continuous function coprime cybernetics cyclic group direct product epimorphism equivalence relation good regulator graph isomorphism graph theory greek language group isomorphism homeomorphism homomorphism if and only if injective function inverse function isometry isomorphism class laplace transform linear map logarithm logical atomism ludwig wittgenstein mathworld mathematical analysis modular arithmetic monomorphism morphism order isomorphism order theory planetmath real number reflexive relation ruler slide rule surjective function symmetric relation topological space total order total relation transitive relation vector space wiktionary