• Argument
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Observations

• "[Plato] defends the solitary, silent nature of the search for episteme--truth: a search that leads one away from the crowd and the multitude. Plato's aim is to take away from the 'majority' the right to judge, choose, and decide."
  (Renato Barilli, Rhetoric. University of Minnesota Press, 1989)
   
• Knowledge and Skill
  "[In Greek usage] episteme could mean both knowledge and skill, both knowing that and knowing how. . . . Each of the artisans, a smith, a shoemaker, a sculptor, even a poet exhibited episteme in practicing his trade. The word episteme, 'knowledge,' was thus very close in meaning to the word tekhne, 'skill.'"
  (Jaakko Hintikka, Knowledge and the Known: Historical Perspectives in Epistemology. Kluwer, 1991)
• Episteme vs. Doxa
  - "Beginning with Plato, the idea of episteme was juxtaposed to the idea of doxa. This contrast was one of the key means by which Plato fashioned his powerful critique of rhetoric (Ijsseling, 1976; Hariman, 1986). For Plato, episteme was an expression, or a statement that conveys, absolute certainty (Havelock, 1963, p. 34; see also Scott, 1967) or a means for producing such expressions or statements. Doxa, on the other hand, was a decidedly inferior expression of opinion or probability. . . .
  
  "A world committed to the ideal of episteme is a world of clear and fixed truth, absolute certainty, and stable knowledge. The only possibility for rhetoric in such a world would be to 'make truth effective'. . .. A radical gulf is presumed to exist between discovering truth (the province of philosophy or science) and the lesser task of disseminating it (the province of rhetoric)."
  (James Jasinski, Sourcebook on Rhetoric. Sage, 2001)
  
  - "Since it is not in human nature to acquire knowledge (episteme) that would make us certain what to do or say, I consider one wise who has the ability through conjecture (doxai) to attain the best choice: I call philosophers those that engage themselves with that from which this sort of practical wisdom (phronesis) is speedily grasped."
  (Isocrates, Antidosis, 353 BC)
   

• Foucault's Concept of Episteme
  "[In Michel Foucault's The Order of Things] the archaeological method attempts to uncover a positive unconscious of knowledge. This term denotes a set of 'rules of formation' which are constitutive of the diverse and heterogeneous discourses of a given period and which elude the consciousness of the practioners of these different discourses. This positive unconscious of knowledge is also captured in the term episteme. The episteme is the condition of possibility of discourse in a given period; it is an a priori set of rules of formation that allow discourses to function, that allow different objects and different themes to be spoken at one time but not at another."
  (Lois McNay, Foucault: A Critical Introduction. Polity Press, 1994)