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Dr. King's audience for the "I Have a Dream" speech was motivated before he began speaking, as they had gathered from across the nation to participate in the March for Jobs and Freedom. As one part of the series of activities intended to urge Congress to enact civil rights legislation, Dr. King's speech was the keynote but not the only presentation of the day.
The speech reflects Dr. King's background and training as a pastor - many of the techniques he uses are good speaking techniques and frequently used with great effect in church settings. He uses repeated phrases for emphasis. Beginning with the phrase "one hundred years later," he presents four different descriptions of the plight of Negro Americans.
He develops an image of cashing "a check" in the minds of the listeners, a process that they all would have understood. He calls the check "a promissory note" that some persons were trying to treat as a "bad check" and refutes that attempt, stating
we refuse to believe that the bank of justice is bankrupt. We refuse to believe that there are insufficient funds in the great vaults of opportunity of this nation. So we have come to cash this check
"Now is the time" - another repeated phrase, written to inspire the crowd to continue working for the end goals of the rally. As an experienced speaker, Dr. King uses techniques such as alliteration to create memorable phrases that are easy to understand and remember, such as "sweltering summer" and "dignity and discipline."
In the repeated statements beginning with "I have a dream," Dr. King paints vivid pictures of situations that would have been very real to the listeners, images that they would have immediately identified with and recognized as wrongs needing to be righted. With each repitition, Dr. King's words added emphasis and heightened the call to action to address the evils in these places.
Concluding with "let freedom ring," coming from the song that would have been familiar to the audience and adding to the song's lyrics to tailor the locations to include places of particular significance to the audience, Dr. King's speech spoke directly to the experiences and concerns of everyone in the audience.
let freedom ring from the prodigious hilltops of New Hampshire. Let freedom ring from the mighty mountains of New York. Let freedom ring from the heightening Alleghenies of Pennsylvania! Let freedom ring from the snowcapped Rockies of Colorado! Let freedom ring from the curvaceous slopes of California! But not only that; let freedom ring from Stone Mountain of Georgia! Let freedom ring from Lookout Mountain of Tennessee! Let freedom ring from every hill and molehill of Mississippi