Page:O. F. Owen's Organon of Aristotle Vol. 1 (1853).djvu/138

, for this may be shown after the same manner as in the former syllogisms. Again, let A be contingent to every B, but let B be necessarily present with every C, there will then be a syllogism wherein A happens to be present with every C, but not (simply) is it present with every C, also it will be complete, and not incomplete, for it is completed by the first propositions. Notwithstanding, if the propositions are not of similar form, first, let the negative one be necessary, and let A necessarily be contingent to no B, but let B be contingent to every C; therefore, it is necessary that A should be present with no C; for let it be assumed present, either with every or with some one, yet it was supposed to be contingent to no B. Since then a negative proposition is convertible, neither will B be contingent to any A, but A is supposed to be present with every or with some C, hence B will happen to be present with no, or not with every C, it was however supposed, from the first, to be present with every C.  Still it is evident, that there may also be a syllogism of the contingent non-inesse, as there is one of the simple non-inesse. Moreover, let the affirmative proposition be necessary, and let A be contingently present with no B, but B necessarily present with every C: this syllogism then will be perfect, yet not of the simple, but of the contingent non-inesse, for the proposition (viz. the contingent non-inesse) was assumed from the major extreme, and there cannot be a deduction to the impossible, for if A is supposed to be present with a certain C, and it is admitted that A is contingently present with no B, nothing impossible will arise therefrom. But if the minor premise be negative when it is contingent, there will be a syllogism by conversion, as in the former cases, but when it is not contingent, there will not be; nor when both premises are negative, but the minor not contingent: let the terms be the same of the simple inesse "white," "animal," "snow," and of the non-inesse "white," "animal," "pitch."

The same will also happen in particular syllogisms, for when the negative is necessary, the conclusion will be of the simple non-inesse. Thus if A is contingently present with no B, but B contingently present with a certain C, it is necessary that A should not be