is B' and 'All B is A.' But if on the other hand 'all' is understood
to form part of the predicate, then u is not really a general but a
singular proposition. When we say, 'All men are rational animals,' we
have a true general proposition, because the predicate applies to the
subject distributively, and not collectively. What we mean is that
'rational animal' may be affirmed of every individual in the class,
man. But when we say 'All men are all rational animals,' the predicate
no longer applies to the subject distributively, but only
collectively. For it is obvious that 'all rational animals' cannot be
affirmed of every individual in the class, man. What the proposition
means is that the class, man, is co-extensive with the class, rational
animal. The same meaning may be expressed intensively by saying that
the one class has the attribute of co-extension with the other.

308. Under the head o u come all propositions in which both subject
and predicate are singular terms, e.g. 'Homer was the author of the
Iliad,' 'Virtue is the way to happiness.'

309. The proposition [eta] conveys very little information to the
mind. 'No A is some B' is compatible with the A proposition in the
same matter. 'No men are some animals' may be true, while at the same
time it is true that 'All men are animals.' No men, for instance, are
the particular animals known as kangaroos.

310. The [omega] proposition conveys still less information than the
[eta]. For [omega] is compatible, not only with A, but with
[upsilon]. Even though 'All men are all rational animals,' it is still
true that 'Some men are not some rational animals': for no given human
being is the same rational animal as any other.