All A is B.
No B is C.
.'. No C is A.
(4) Partial exclusion on the ground of including the whole of an excluded term (Fesapo).
[Illustration]
No A is B.
All B is C.
.'. Some C is not A.
(5) Partial exclusion on the ground of including part of an excluded term (Fresison).
[Illustration]
No A is B.
Some B is C.
.'. Some C is not A.
§ 638. It is evident from the diagrams that in the subaltern moods the conclusion is not drawn directly from the premisses, but is an immediate inference from the natural conclusion. Take for instance AAI in the first figure. The natural conclusion from these premisses is that the minor term C is wholly contained in the major term A. But instead of drawing this conclusion we go on to infer that something which is contained in C, namely some C, is contained in A.
[Illustration]
All B is A. All C is B. .'. all C is A. .'. some C is A.