JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. Association for Symbolic Logic is collaborating with JSTOR to digitize, preserve and extend access to The Journal of Symbolic Logic.In this paper we show the finite controllability of the Maslov class of formulas of pure quantification theory (specified immediately below). That is, we show that every formula in the class has a finite model if it has a model at all. A signed atomic formula is an atomic formula or the negation of one; a binary disjunction is a disjunction of the form Al v A2, where Al and A2 are signed atomic formulas; and a formula is Krom if it is a conjunction of binary disjunctions. Finally, a prenex formula is MVaslov if its prefix is 3*-3V. --... * 3 and its matrix is Krom. A number of decidability results have been obtained for formulas classified along these lines. It is a consequence of Theorems 1.7 and 2.5 of [4] that the following are reduction classes (for satisfiability): the class of Skolem formulas, that is, prenex formulas with prefixes v... * *-* *3, whose matrices are conjunctions one conjunct of which is a ternary disjunction and the rest of which are binary disjunctions; and the class of Skolem formulas containing identity whose matrices are Krom. Moreover, the following results (for pure quantification theory, that is, without identity) are derived in [1] and [2]: the classes of prenex formulas with Krom matrices and prefixes 3V3V, or prefixes V33V, or prefixes V3VV are all reduction classes, while formulas with Krom matrices and prefixes V3V comprise a decidable class. The latter class, however, is not finitely controllable, for it contains formulas satisfiable only over infinite universes. The Maslov class was shown decidable by Maslov in [11].The basis of our proof is the construction of finite universes with certain combinatorial properties; this is done in ?1 by generalizing two lemmas devised by G6del in his finite controllability proof for prenex formulas with prefixes V3 ... 3 [9]. In ?2 we show that we need only consider those Maslov formulas in Skolem form whose matrices satisfy two special truth-functional conditions. Finally, in ?3 we define, for any formula of this form whose matrix is truth-functionally consistent, a model over a finite universe with the combinatorial properties given in ?1. Since consistency of the matrix is necessary for the satisfiability of a formula, the finite controllability of the full Maslov case is thereby established.?1. A model for an arbitrary satisfiable Skolem formula F = Vy1 --Vyn3x, *.. 3xmM can be obtained by starting with a suitable universe U and functionsfj: Un U for j = 1, --*, m, and then defining a truth-assignment s' to atomic formulas with Received July 11, 1973.