Confusion in the Classroom: Does Logos Mean Logic?
http://baywood.metapress.com/link.asp?target=contribution&id=7ATYRVVU53FJMVC5
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Little, Joseph
Journal of Technical Writing and Communication
1999

Abstract:

The redefinition of logos as an appeal to logic is a mistaken association found all too often in the technical communication classroom. Logic inheres in all three proofs of persuasion; moreover, Aristotle used <em>logos</em> within the context of classical rhetoric to refer to the argument or speech itself. In this light, the proofs of persuasion represent the set of all logical means whereby the speaker can lead a "right-thinking" audience to infer <em>something</em>. If that <em>something</em> is an emotion, the appeal is to <em>pathos</em>; if it is about the character of the speaker, the appeal is to <em>ethos</em>; and if it is about the argument or speech itself, the appeal is to <em>logos</em>. This interpretation reinstates all three proofs of persuasion as legitimate, logical means to different proximate ends and provides a coherent definition of <em>logos</em>, consonant with Aristotle's <em>Rhetoric</em>, to the next generation of technical communicators.