Grimaldi's Note on the Pisteis in Aristotle's Rhetoric, A Brief Summary

Traditionally, the pisteis entechnoi have been defined as ethos, pathos, and logos, where ethos and pathos have been equated with non- or quasi-logical, and where logos has been equated with the logical and the enthymeme. But the way Aristotle uses the word pistis has no univocal meaning and is difficult to define, and what he actually means is much more nuanced. Furthermore, the misunderstanding of the different meanings of pistis have created much confusion and many seeming inconsistencies. In this article, Grimaldi analyzes sections 1354-1356 from Aristotle’s Rhetoric to give three different meanings of the word pistis: 

1. first, pistis is source material that can induce belief in an audience. This is where we find the atechnoi and entechnoi pisteis, which Grimaldi calls ethos, pathos, and pragma. 
2. Second, pistis is the method whereby the source material is used to produce pistis in the audience. This pistis, like episteme, is the result of demonstration. It is under this definition of pistis where enthymemes and paradigms are employed. 
3. Finally, pistis is the state of mind—belief—that has been produced or induced in the audience.

So, depending on how we define pistis, we will be talking about something slightly different. If pisteis are source materials for proofs, then those proofs lie in ethos, pathos, and pragma. But if pisteis are modes of demonstration, then they are enthymemes and paradigms. Hence, Grimaldi argues that the enthymeme must not be equated with the third definition of pistis, but the enthymeme instead employs the pisteis entechnoi, the source material. The enthymeme thus embodies the pisteis, giving them form so they can be used to persuade an audience. [And now I wonder if we can say something like induce belief.]

Grimaldi also recognizes that ethos and pathos are not non- or quasi-logical because as human beings, we make judgments and accept propositions with feelings, emotions, will, character, and intellect. 

From Grimaldi, William M. A. 1957. “A Note on the Pisteis in Aristotle’s Rhetoric, 1354-1356.” The American Journal of Philology 78(2): 1957, pp. 188-192.