37. Third Classification of Propositions: According to Their Quantity. -- A proposition is universal, singular (or particular), indefinite.

(1) The universal proposition asserts that an attribute belongs to all the subjects of an idea or to none of them. As: All men are mortal; No man fatally misses his destiny.

(2) The singular proposition enunciates an attribute of one individual. When the subject represents a determinate group of individuals, it is collective: in the logical point of view it is of the same nature as the singular subject. We also call all those propositions particular the subject of which is not universal, whether it include many individuals of the same species or only one. As: Some men are learned; the Belgian people is active.

(3) The indefinite proposition expresses the agreement or nonagreement of a predicate and a subject without expressly saying whether the subject is taken in all its extension or only in part of it. As: They have been unjust in this matter.

The universal proposition is more important than the particular. The former, indeed, contains the latter in its extension; to know the former is virtually to know the -latter; but the converse is not true.