The three modes of persuasion logos, ethos and pathos originally come from Ancient Greece, where philosophers and politicians were typically very interested in studying the rhetorical principles of debate and persuasion. The modes describe three different strategies that a speaker can use to make a speech convincing. They are also known as rhetorical appeals.
It is often highly relevant to consider the modes of persuasion when analyzing a speech, as they can tell you a lot about how the speech affects its audience - in other words, how it appeals to them.
Generally speaking, logos refers to strategies that appeal to the audience’s reason. Ethos refers to strategies that appeal to the audience’s trust in the speaker. Finally, pathos refers to strategies that appeal to the audience’s emotions. Speakers will often draw on all of these rhetorical modes in their speeches, but often some dominate more than the others.
You can read more about how each mode works on the following pages.
If you want a detailed, example-based description of the three forms of appeal, you can read our webbook dedicated to this topic.