Some men are mortal—Particular.
Man is mortal—Indefinite.
 John Stuart Mill, A System Of Logic, Ratiocinative And Inductive (1843). copy citation

Context

“The next of the common divisions of Propositions is into Universal, Particular, Indefinite, and Singular: a distinction founded on the degree of generality in which the name, which is the subject of the proposition, is to be understood. The following are examples: All men are mortal—Universal. Some men are mortal—Particular. Man is mortal—Indefinite. Julius Cæsar is mortal—Singular. The proposition is Singular, when the subject is an individual name. The individual name needs not be a proper name. “The Founder of Christianity was crucified,”” source