 Other philosophers reject Prawitz's (and Gentzen's) view that the introduction rules have priority in fixing the meanings of constants, but retain the idea that the introduction and elimination rules that fix the meaning of a constant must be in harmony: the elimination rules must not permit us to infer more from a compound sentence than would be justified by the premises of the corresponding introduction rules (Dummett 1981, 396; Tennant 1987, 76-98). (For analyses of various notions of harmony, and their relation to notions like normalizability and conservativeness, see Milne 1994, Read 2010, and Steinberger 2011.) 