These three concepts constitute Aristotle’s appeals: ethos, an appeal to character; pathos, an appeal to emotion; and logos, an appeal to logic. Although these rhetorical strategies have a longstanding history, this three-pronged model does not effectively represent honest rhetoric.
Ethos usually manifests as an appeal to authority, in which the author explains that his argument comes from a credible source and is therefore correct. This is not a distinct type of argument, but actually a subset of logos. An appeal to authority, when done properly, forms a logical argument:
1. This authority figure is usually correct on this subject.
2. This authority figure claims X is true.
3. Therefore, X is probably true.
Of course, an appeal to authority can be done improperly, such as when it uses a non-expert or makes a more strict claim than it can (i.e., this authority figure claims X is true, therefore X must be true). Such incorrect applications are fallacious. But when used correctly, an appeal to authority—ethos—is simply a type of logos.
Sometimes, ethos may represent the reverse: an attempt to demonstrate that one’s opponent is not credible—an argument ad hominem. This type of argument is nearly always fallacious. And in this case as well, if it is not fallacious then it can be expressed as a logical argument and is therefore a subset of logos.
Of Aristotle’s three strategies, pathos has the least sway. An appeal to emotion is a logical fallacy: it represents an attempt to subvert the reader’s sense of reason. According to Fallacy Files, “Appeals to emotion are always fallacious when intended to influence our beliefs, but they are sometimes reasonable when they aim to motivate us to act.” (More on this second clause in a future essay.)
The emotional appeal probably occurs more frequently than any other logical fallacy, but that makes it no less fallacious. A strong rhetorician makes frequent use of emotional appeals, but an honest debater uses emotion only as a supplement to logical argumentation, and only, as Fallacy Files explains, to motivate the reader to action.
Logos—the appeal to logic—represents the only true means of argumentation. Any other form of argument is, by definition, unsound. Logos is the only of Aristotle’s appeals that holds serious rational merit, and therefore deserves the greatest consideration. Ethos and pathos do not deserve to rest on the same plane as logos; any non-logical form of argumentation exists either to supplement or to subvert logic.
A Better Model
Sound argument rests not on three pillars, but on one: the pillar of logic. But there is no reason to consider argumentation as a single thing: one could devise a number of models to represent the process of rational thought in different terms. It could be represented as the unity of pure reason a priori and factual information a posteriori; it could be thought of as a logical core with branches representing the myriad logical fallacies. Either of these models would make a more effective model than Aristotle’s appeals, and surely there exist even better models than these.
Instead of teaching Aristotle’s rhetorical devices to debaters and writers, we should teach how to speak and write persuasively without resorting to logical fallacies, and how to identify and respond to fallacious reasoning when others use it. If people understand how to form strong logical arguments and avoid emotional appeals and reactions, we as a society will be empowered to make wiser decisions—and side with the people who are the most correct rather than the most persuasive.