Greek philosopher Aristotle outlined three persuasive “proofs” that are still used today.

Ideas about establishing credibility as a speaker aren’t new to us in the 21st century. Persuasion is a subject that has been studied by human beings around the world for thousands of years. Principles of persuasive public speaking were developed by scholars in places like China, Africa, Greece, and Rome. Many of the principles of effective argumentation we study today were first developed in ancient Greece and refined by teachers of public speaking in the Roman Empire.

Greek philosopher Aristotle wrote the first “textbook” on persuasion in the Western world, The Rhetoric. In The Rhetoric, Aristotle differentiated between different modes of persuasion speakers use. For Aristotle, there were two categories of persuasive modes: inartistic and artistic proofs. Inartistic proofs are resources like physical evidence that a speaker has access to. In contrast, artistic proofs are created by the speaker.

The three artistic proofs Aristotle identified are:

• Ethos: The speaker’s character. Ethos involves the way a speaker conveys to the audience that they can be trusted. Ethos includes evidence of good sense (what the Greeks called phronesis or practical wisdom), evidence of good will (called eunoia, enlightened self interest or good of the community), and evidence of good moral character (called arete, moral excellence).
• Pathos: The emotions the speaker is able to appeal to and awaken in their audience.
• Logos: Use of reasoning. Proving a truth or apparent truth by means of logical arguments suitable to the case in question.

Credible speakers make well-rounded arguments that involve a combination of ethos, pathos, and logos. They’re not the only ones, though! Since these three persuasive “proofs” are so powerful, nearly anyone trying to convince you of something will probably use one or more of the three. The short video below outlines some of the ways advertisers use ethos, pathos, and logos to sell products.