Ethos, pathos, logos

The definition of Ethos;
In classical rhetoric, a persuasive appeal (one of the three artistic proofs) based on the character or projected character of the speaker or writer.

Example;

"Everyone makes an appeal to ethos, if only an ethos of choosing never to stoop to such matters as ethos. No speech with intent is 'non-rhetorical.' Rhetoric is not everything, but it is everywhere in the speech of human arguers."
(Donald N. McCloskey, "How to Do a Rhetorical Analysis, and Why." New Directions in Economic Methodology, ed. by Roger Backhouse. Routledge, 1994)

The definition of Pathos;
In classical rhetoric, the means of persuasion (one of the three artistic proofs) that appeals to the audience's emotions. Adjective: pathetic.

Example;
"Hillary Clinton used a moment of brilliantly staged emotion to win the New Hampshire Democratic primary . . .. As she answered questions in a diner on the morning before the election, Mrs. Clinton's voice began to waver and crack when she said: 'It's not easy. . . . This is very personal for me.

The definition of Logos;
In classical rhetoric, the means of persuasion by demonstration of logical proof, real or apparent. Plural: logoi.

Example;

"The appeals to reason that an orator might use do not violate the principles of strict logic; they are merely adaptations of logic. So, whereas the syllogism and induction are the forms that reasoning takes in logic, the enthymeme and the example are the forms that reasoning takes in rhetoric."
(Edward P.J. Corbett and Robert J. Connors, Classical Rhetoric for the Modern Student. Oxford Univ. Press, 1999)