In this case, they are expository: that is, they are intended to elicit a particular response in the audience. For example, although Abraham Lincoln 's speech took place at the dedication of a grave, his speech spun the situation to his advantage. In the third paragraph of Lincoln 's speech, he segues from dedicating the grave into advancing his own agenda. Essentially, he says that the dead should be honoured through achieving the goal they died for, i.e. winning the civil war, and repeats this point multiple times. This is an effective argument as it feeds the emotion of the situation into his goal - his final call to action is to 'resolve that these dead shall not have died in vain '. It is very clear what the purpose of the speech is.
Similarly, MLK 's speech was designed to vindicate his supporters and gain him new ones, particularly people in positions of power. This is evident in his calls of action directed at white people, and his drawing of awareness to the suffering of his. For example, the entire paragraph repeating "We cannot be satisfied", listing examples of injustice. This wins sympathy from those who have experienced it and ensures people who haven 't know it is there. Neither of the speeches were designed to "go down in history" on their own merits. This was not their …show more content…
It is true this relates to its effectiveness as a text - however, that is not the most important reason. It is largely circumstance that has helped it remain memorable. Its themes, concerning both racism and overall equality, are still relevant today. Its historical context is very important. The speech was also made in 1963, a little over half a century ago. This is recent enough both that video record of it exists and that living people remember seeing it live. These things have very little relation to the actual quality of the speech - however, if they were not true, it could have been entirely forgotten despite its language. A speaker may, for example, try to control whether their speech will continue to be relevant by speaking on a more general, universal topic. However, in what way does this make it "better" than a more topical speech? How a piece of media is remembered can depend on any number of random factors, and it seems unreasonable to judge quality based on this.
A persuasive speech is a product of its context and usually tailored to a specific purpose. As it is a one-time performance existing for a reason, its main value lies in its ability to accomplish its goal. Long after its creation, it may still be remembered and regarded like a work of art. However, if this does not happen, it does not diminish its value, and if it does, its importance is still firmly rooted in a historical context.