"I have a dream."

Today is a good day to visit American Rhetoric, which has a page devoted to Martin Luther King Jr.'s "I have a dream" speech, including both a video and the text of the speech. Besides being historic and inspirational, the speech is a fine example of rhetoric — in this case rhetoric in the service of moral persuasion. (Hat tip to Slaw.ca.)

A good example of Dr. King's rhetorical writing is his Letter from a Birmingham Jail. This letter is Dr. King's response to southern clergymen who questioned the wisdom and timeliness of his protests. In the letter, Dr. King employs rhetoric not only to justify the righteousness of his own actions, but also to prick the conscience of the clergymen. This too is a textbook example¹ of rhetoric used for moral persuasion.
__________
¹ The textbook is Classical Rhetoric for the Modern Student, pp. 301-19 and 478-83 (4th ed. 1999), by Edward P.J. Corbett and Robert J. Connors.