how does martin luther king jr.'s use of metaphor in this passage from his nobel peace prize acceptance speech affect his tone

It makes the speech more poetic

Explanation

a metaphor is a figure of speech that consists in making a direct comparison between elements that aren't obviously related, in order to create an image in the reader's mind. The given lines from Martin Luther King Jr.'s  Nobel Peace Prize acceptance speech we can see an example of a metaphor that compares justice with a wounded person, this metaphor helps to make the speech more poetic.

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