One discusses valid syllogisms (VS), sorites, “distribution conservation”, empty setconstraints (ESC), and one compares the Classic Categorical Syllogistic (CCS) with a SetTheoretical Model (STM). A valid categorical argument (VCA) is a pair of categoricalpremises (PCP) together with its entailed logical consequence (LC). CCS defines a VS as aVCA which satisfies the supplementary conditions that the PCP be formulable using only the“positive” S,P,M terms, and that the LC - obtained via existential import (ei) or not - be one ofthe A(S,P), O(S,P), E(S,P) or I(S,P) statements. Therefore, in CCS, the P term has to be thepredicate of the LC. Both the CCS moods and figures notation, and the STM PCP matrixnotation use the convention that in a PCP one firstly lists the P-premise. STM interprets theS,P,M terms as sets, and also allows the “negative” terms, non-S, non-P, non-M, (denoted byS',P',M' – the complementary sets in a universal set U to S,P,M, respectively), to appear in thePCPs and LCs. To characterize a VCA, STM does not use syllogistic figures, the condition ofP term being the predicate of the LC, the automatic removal of the middle term from anyentailed LC, nor the rules of valid syllogisms (RofVS). In STM any LC pinpoints to just oneand only one of the eight subsets partitioning U, as either being definitely not empty, (Dariitype LC), or, as being the only one subset possibly non empty of either one of the sets S,P,S',P',(Barbara/Barbari type LC), or of one of the sets M,M' (Darapti type ei LC). A tree like methodimmediately finds the LC of a any VCA.