The Converse, then, of _Some ruminants are not hollow-horned_ must be a negative proposition, having 'hollow-horned' for its subject, either in E.or O.; but these would be respectively the contrary and contradictory of _All hollow-horned animals are ruminants_; and, therefore, if this be true, they must both be false.
But (referring still to Fig.

1) the legitimacy of contrapositing O.is equally clear; for if _Some ruminants are not hollow-horned_, _Some animals that are not hollow-horned are ruminants_, namely, all the animals between the two ring-fences.

Similar inferences may be illustrated from Figs.

3 and 4.

And the Contraposition of A.may be verified by Figs.