quantity of a term is determined or undetermined, and afterwards
proceeding to inquire, whether it is determined as a whole or part of
its possible extent. As it is, to say that a term is distributed,
involves two distinct statements--

(1) That its quantity is known;

(2) That its quantity is the greatest possible.

The term 'undistributed' serves sometimes to contradict one of these
statements and sometimes to contradict the other.

279. With regard to the quantity of the subject of a proposition no
difficulty can arise. The use of the words 'all' or 'some,' or of a
variety of equivalent expressions, mark the subject as being
distributed or undistributed respectively, while, if there be nothing
to mark the quantity, the subject is for that reason reckoned
undistributed.

280. With regard to the predicate more difficulty may arise.

281. It has been laid down already that, in the ordinary form of
proposition, the subject is used in extension and the predicate in
intension. Let us illustrate the meaning of this by an example. If
someone were to say 'Cows are ruminants,' you would have a right to
ask him whether he meant 'all cows' or only 'some.' You would not by
so doing be asking for fresh information, but merely for a more
distinct explanation of the statement already made. The subject being
used in extension naturally assumes the form of the whole or part of a
class. But, if you were to ask the same person 'Do you mean that cows