An essay on the history and usage of paragraphs in English writing by Edwin Herbert Lewis, submitted as his PhD thesis to the University of Chicago.
The name of the typograpical mark used to indicate a paragraph is the Pilcrow: ¶Historically considered, the word paragraph means (a) a marginal character or note employed to direct attention to some part of the text; (b) a character similar to (a), but placed in the text itself; (c) the division of discourse introduced by a paragraph mark or by indentation, and extending to the next paragraph mark or the next indentation; (d) the rhetorical paragraph, that is, (c) developed to a structural unit capable of organic internal arrangement.
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