This late 20th-century movement is best characterized for its overall rejection or suspicion of what it is established in society (the authority, traditional religious practices, traditional logic, the education system, etc.), and instead it promotes subjectivism and relativism claiming that there is not "right" way of doing things, or there isn't an only "truth" but several, therefore this movement encourages people to experiment a lot, to try with anything new, to make mistakes, etc. The limits of post-modernists artists are very wide (if there are any) and they tend to base their works in untested and innovative ideas and techniques, this is why "Experimental" is the most accurate feature to describe this movement.
Dr. Martin Luther King Jr's I Have A Dream speech was more of an argumentative speech, as well as a speech that was persuading the listener to understand.
