L. Descalço on the Injectivity of the Leibniz Operator
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چکیده
The class of weakly algebrizable logics is defined as the class of logics having monotonic and injective Leibniz operator. We show that “monotonicity” cannot be discarded on this definition, by presenting an example of a system with injective and non monotonic Leibniz operator. We also show that the non injectivity of the non protoalgebraic inf-sup fragment of the Classic Propositional Calculus, CPC∧∨, holds only from the fact that the empty set is a CPC∧∨-filter.
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تاریخ انتشار 2005