are all the ruminants that there are, or only some of them?' he would
have a right to complain of the question, and might fairly reply, 'I
did not mean either one or the other; I was not thinking of ruminants
as a class. I wished merely to assert an attribute of cows; in fact, I
meant no more than that cows chew the cud.'

282. Since therefore a predicate is not used in extension at all, it
cannot possibly be known whether it is used in its whole extent or
not.

283. It would appear then that every predicate is necessarily
undistributed; and this consequence does follow in the case of
affirmative propositions.

284. In a negative proposition, however, the predicate, though still
used in intension, must be regarded as distributed. This arises from
the nature of a negative proposition. For we must remember that in any
proposition, although the predicate be not meant in extension, it
always admits of being so read. Now we cannot exclude one class from
another without at the same time wholly excluding that other from the
former. To take an example, when we say 'No horses are ruminants,' the
meaning we really wish to convey is that no member of the class,
horse, has a particular attribute, namely, that of chewing the
cud. But the proposition admits of being read in another form, namely,
'That no member of the class, horse, is a member of the class,
ruminant.' For by excluding a class from the possession of a given
attribute, we inevitably exclude at the same time any class of things
which possess that attribute from the former class.

285. The difference between the use of a predicate in an affirmative