There are many ways in which the use of a rhetorical question can help develop a speaker's ideas. One of the ways in which this is accomplished is by emphasizing the points that the author makes in a text. By asking rhetorical questions, he can show how good his points are compared to the alternatives. Moreover, a rhetorical question allows the audience to feel more engaged with the text, making the experience more dynamic and interesting.
One (internal) is from your thoughts or the characters thoughts and the other one (external) is from what is actually happening to or around the character.
