Pathos- Martin Luther King uses pathos in his speech. "Rise from the dark and desolate valley of segregation to the sunlit path of justice," is one example of how he uses pathos. He uses many appeals to emotion in order to persuade the audience to support his cause. He continues to speak about discrimination, which can be an emotional topic for the audience. Police brutality is also a part of discrimination as he says in this quote, "Negroes are the victims of the unspeakable horrors of police brutality." All of the subjects that he speaks about are emotional topics.
Logos- He does a good job of using logos throughout his "I Have a Dream" speech. He uses the "Emancipation Proclamation" as a reference to get the audience into the mindset of equal rights for all. Martin Luther King refers to voting rights as another example of unalienable rights that are not equal for all. He frequently made religious mentions such as this one, "Now is the time to make justice a reality for all of God's children." He was fighting for equal rights without physical violence.
Ethos- Martin Luther King references the Emapncipation Proclaimation as a beacon of hope. He shows his beliefs by saying "Let us not seek thirst for freedom by drinking bitterness and hatred." This explains how he wants the quest for freedom to be as peaceful and non-violent as possible. He then goes on to say how the struggled should be conducted with dignity and discipline. Throughout the speech Martin Luther King mentions the Constitution as a credible document to back up his reasoning.