... Sarah. The name girl is held in common by all girls, and hence does not distinguish one girl from another. The name Sarah is not thus held in common; it does distinguish one girl from other girls. Any name which belongs in common to all things of a class we call a Common Noun; and any particular name of an individual, distinguishing this individual from others of its class, we call a Proper Noun. The "proper, or individual, names" which in Rule 1, Lesson 8, you were told to begin with capital letters are ... — Higher Lessons in English • Alonzo Reed and Brainerd Kellogg
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