“Through its contrasting river and shore scenes, Mark Twain’s Huckleberry Finn suggests that to find the true expression of American freedom, one must leave ‘civilized’ society and go back to nature.”
Note how this thesis presents a substantive interpretation of a literary work based on an analysis of its content as well as an assessment of its significance (i.e., it answers the “so what?”/ “what is at stake?” question of the text’s purpose/meaning). Arguments based on other kinds of texts beyond literature should still seek to synthesize those sources together to make a specific, nuanced claim that holds across all of them.