Fraenkel–Carnap Questions for Equivalence Relations
نویسنده
چکیده
An equivalence is a binary relational system A = (A, ρA) where ρA is an equivalence relation on A. A simple expansion of an equivalence is a system of the form (Aa1 an) were A is an equivalence and a1, . . . , an are members of A. It is shown that the Fraenkel–Carnap question when restricted to the class of equivalences or to the class of simple expansions of equivalences has a positive answer: that the complete second-order theory of such a system is categorical, if it is finitely axiomatizable.
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تاریخ انتشار 2011