Review of: Bruce Tesar & Paul Smolensky (2000): Learnability in Optimality Theory. by Paul Boersma, University of Amsterdam January 17, 2004 This review is not only for people interested in learnability in OT, but for everybody who believes in OT's claim of factorial typology, i.e. the prediction that all language types generated by a permutation of the rankings of the constraints are attestable human languages. Learnability considerations are capable of shooting holes in that claim.