... indifferently for either of the othersymbols, then each of the equations of the premises of any given syllogism may be put in the formay + bx = 0, (α)if the premiss is affirmative, and in the formay + b(1 ... not-Xs, the resulting Propositions beingAll not-Ys are not-Xs,Some not-Ys are not not-Xs. (a)Or we may, by simply inverting the order of the factors in the secondmember of O, and writing it in the ... 0,—adequately represents the logicalcondition of there being no middle term, or common medium of compari-son, in the given premises.I am not aware that the distinction occasioned by the presence or...