How does Martin Luther King, Jr. establish credibility (ethos) in the "I Have a Dream" speech?

Opening his speech Martin Luther King Jr. sets up his credibility with his use of ethos, referring to the Declaration of Independence saying, “This note was a promise that all men… would be guaranteed the unalienable rights of life.”

Explanation:

answer: alexander the great

explanation:

a social contract.

"a social contract is an agreement between citizens and their leader where the citizens give up certain freedoms in exchange for protection. the constitution of the united states is an example of a social contract."