John Locke

(August 29, 1632 - October 28, 1704)

 From a Library of Congress lithograph

(Public Domain image and caption from Wikimedia Commons)

Locke On Rhetoric 

“The ends of language in our discourse with others being chiefly these three: First, to make known one man’s thoughts or ideas to another.  Secondly, to do it with as much ease and quickness as possible; and, Thirdly, thereby to convey the knowledge of things: language is either abused or deficient, when it fails of any of these three.   (from "An Essay Concerning Human Understanding," vol.2, bk.3, ch.10, sec.23) 

"Wit and fancy get a better welcome in the world than dry truth and real knowledge; so people will hardly think that the use of figurative language and ·literary· allusion constitutes an imperfection or misuse of language. In contexts where we seek pleasure and delight rather than information and improvement, such ornaments are indeed not faults. But if we want to speak of
things as they are, we must allow that all the art of rhetoric (except for order and clearness) - all the artificial and figurative application of words that eloquence has invented - serve only to insinuate wrong ideas, move the passions, and thereby mislead the judgment; and so they are perfect cheats. . . . It is evident how much men love to deceive and be deceived, since rhetoric - that powerful instrument of error and deceit - has its established practitioners, is publicly taught, and has always been highly regarded. No doubt I will be thought rash or oafish to have spoken against it. . . . " (from "An Essay Concerning Human Understanding," vol.2, bk, 3, ch.10, sec, 34. )