The same tools that let you persuade honestly are the tools that let you spot a lie dressed up well.
Rhetoric began as a practical skill in the Greek courts and assemblies — how to argue a case, move a crowd, win a vote — before Aristotle gave it its first systematic theoretical treatment, treating persuasion as something that could be studied and taught with the same rigor as logic, built on credibility, reasoned argument, and emotional appeal working together. As the third leg of the trivium, it assumed a student had already mastered grammar (how language means) and logic (how arguments hold), and asked them to apply both toward moving another mind.
The discipline’s later history runs through Roman education, medieval university training in disputation, and into the modern study of communication and media — the same three-part structure (credibility, logic, emotion) still used today to analyse advertising and political speech traces directly back to this Aristotelian framework.
Source: Kennedy, G.A. (1963). History of Rhetoric, Volume I. Princeton University Press.