They allow you to associate concepts with concrete images and emotions, or to highlight the differences between the abstract concepts by contrasting them with the concrete mental pictures, for example to compare segregation with racial justice, Martin Luther King uses the phrase “rise from the dark and desolate valley of segregation to the sunlit path of racial justice”. People will associate the words dark and desolate valley to a gloomy, dark unwelcoming place surrounded by walls that you can not get out of, however by using the words sunlit path of racial justice creates the image of a bright happy and open area. In general terms dark and desolate have nothing to do with the work segregation and neither sunlit with racial justice, but by wording it this way it shows people that the dark and hideous place of segregation is where we don’t want to be, but a happy and cheerful place of racial justice? That’s what we want and that’s where we need to be. Metaphors however aren’t the only language device that creates mental images in the audience’s heads.
Persona is in a sense the mask the author wears to adopt a certain role, which the audience will be able to relate to in some way. The way in which a persona is used will ultimately affect how the audience responds to the information. Martin Luther King Jr changes his persona at almost every paragraph. He does this so to keep the interest of both the white and black people in the audience but to also show that there is more than just one side to a person, therefore they should not be judged by one characteristic. “Five score years ago, a great American, in whose shadow we stand today, signed