(with John K. Slaney and Robert K. Meyer) “Linear Arithmetic Desecsed,” *Logique et Analyse,* 39 (1996) 379–388 (published in 1998).

In classical and intuitionistic arithmetics, any formula implies a true equation, and a false equation implies anything. In weaker logics fewer implications hold. In this paper we rehearse known results about the relevant arithmetic R#, and we show that in linear arithmetic LL# by contrast false equations never imply true ones. As a result, linear arithmetic is *desecsed*. A formula *A* which entails 0=0 is a *secondary equation*; one entailed by 0≠0 is a *secondary unequation*. A system of formal arithmetic is *secsed* if every extensional formula is either a secondary equation or a secondary unequation. We are indebted to the program `MaGIC` for the simple countermodel **SZ7**, on which 0=1 is not a secondary formula. This is a small but significant success for automated reasoning.

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