The correct answer to this open question is the following.
Although you did not mention what speech you are referring to, we assume that is the speech that Franklin delivered during the Constitutional Convention. If this is the case, then the answer is the following.
Franklin’s purpose for writing this speech was to express his feelings about the ideas portrayed in the Constitution. The language he used was carefully chosen by Franklin. He was an intellectual, a man of the US Enlightenment that knew very well what he wanted to convey with his ideas. His tone is firm, direct, backed with the proper arguments to support his feelings. He insisted on the idea that people´s opinions were what count. The will of people.
Benjamin Franklin was so capable to include the kind of language to make people think and the "ethos" factor to move to reflection and convince. His speech was powerful and persuasive to the degree that today is still a good speech to have it for reference.
During the Constitutional Convention held in the city of Philadelphia, Pennsylvania during the summer of 1787, the delegates debated and argued about the new form of government needed for the United States.
You forgot to mention that this question is about Franklin's speech at the Constitutional Convention.
Answer and Explanation:
Franklin's purpose with this speech was to show that changes in the articles of the confederation may seem controversial to some people, including himself, but that does not mean that these changes should not be supported and that these changes must be accepted by all, because they are the result of the thinking of many wise men who have the same objective, to care for and establish a strong and efficient country.
For that, he used simple and direct words, but formal and respectful and persuasive, used a serious but friendly tone and showed his point of view on the creation of the constitution. For him the constitution is beneficial, even if it presents points that may not cover everyone's will.
