Tell, Håkan. 2011. Plato's Counterfeit Sophists. Hellenic Studies Series 44. Washington, DC: Center for Hellenic Studies. http://nrs.harvard.edu/urn-3:hul.ebook:CHS_Tell.Platos_Counterfeit_Sophists.2011.
2. Wisdom for Sale? The Sophists and Money
Sophists and Money in the Platonic Tradition
It should be clear that if Plato is not outright condemning the sophists for taking fees, he is also not using a value neutral language when describing their practices. Far from it: they are regularly portrayed as more interested in procuring material rewards for their services than in worrying about the intellectual content or effect of their sophia. All this is in sharp contrast to his characterization of Socrates in the Apology, where Socrates’ commitment to wisdom and the moral development of his fellow citizens has reduced him to all but total poverty. This hostile attitude towards the sophists is picked up and further elaborated by Xenophon and Aristotle. In the Cynegeticus (13.8–9), for example, Xenophon asserts that:
The phrase πλουσίους καὶ νέους θηρῶνται echoes the line νέων πλουσίων … θήρα of the Sophist quoted above, and the thematic content of the passage—that the sophists prioritize money over wisdom and are thus undeserving of serious intellectual consideration—is perfectly in line with Platonic sentiments. Aristotle makes the same connection in the Sophistical Refutations (165a22): “The sophist is a trafficker (χρηματιστής) in what seems to be, but is not, wisdom (σοφία).” In the Memorabilia (1.6.13), Xenophon employs a double strategy of first asserting and then condemning what he sees as an inherent connection between money and wisdom (the latter predicated on the former) among the sophists. But this time he adds an extra layer of opprobrium by expanding on the cultural implications associated with offering one’s personal qualities for sale:
Here Xenophon establishes a thematic sequence consisting of wisdom, money, and prostitution, in which the interference of the intermediary phase—money—runs the danger of corrupting and even conflating the things of the mind with the sphere of the body.  This is, of course, exactly the opposite trajectory of what we are wont to see in Plato.  In the Symposium and the Alcibiades I, for example, love (ἔρως) is restricted to using the physical as an initial stepping stone only to climb the philosophical ladder and ultimately reject the body in favor of the mind, thus gradually transforming itself from a physical, sexual desire directed at a specific individual to a generic non-physical love of the beautiful.  By reversing this trajectory and by introducing the concept of intellectual promiscuity, Xenophon invites us to appreciate the contentiousness of his portrayal of the sophists. In this antagonistic depiction the mention of teaching for money is crucial in allowing the association of sophistic sophia with the body and, ultimately, with prostitution. Read in this way, teaching for pay takes on a more sinister facet than has previously been recognized, and it paves the way for the successive ubiquitous complaints of the speciousness of sophistic wisdom.
Themistius understands Plato’s definition of sophist to include anyone who teaches for pay, regardless of the content of the instruction:
In Themistius’ mind, then, the sole criterion for distinguishing a sophist hinges on whether he charges money for instruction. Considerations of intellectual content (e.g. rhetoric vs. dialectic; relativism vs. idealism) are of less relevance than this formal characteristic. To Themistius, just as to Socrates in the passage from Xenophon’s Memorabilia quoted above (1.6.13), the pecuniary focus of the sophists inevitably disqualifies them from being considered serious philosophers and consigns them to the sphere of the body. Themistius is careful to highlight the difference between himself, who improves both the body and the mind of his students, and the sophists, whose focus is exclusively on the body:
A little later Vlastos revisits the issue of the dialogue’s inauthenticity and writes:
But there is a case to be made that the two portrayals of Zeno in the Alcibiades I and Parmenides are not necessarily incompatible.  To begin with, in the Parmenides 128b–e Zeno says that he wrote his book in a youthful competitive spirit and that it was later published through unauthorized copying. This seems to imply that to Plato Zeno’s work was predominantly eristic in nature and had more affinities with the sophists than with philosophers. In Phaedrus 261b–e it is presumably Zeno who is intended by the epithet “the Eleatic Palamedes” whose rhetorical skill is such that “his listeners will perceive the same things to be both similar and dissimilar, both one and many, both at rest and also in motion” (trans. Gill and Ryan). This portrayal reinforces the picture from the Parmenides that to Plato Zeno’s work was predominantly eristic in character, and it does not seem entirely unreasonable to think that Plato regarded him as a sophist. The question remains why Vlastos would find the Zeno-sophist portrayal incompatible with his characterization as “Parmenides’ right-hand man.”
Sophists and Money in Old Comedy and Isocrates
Far from singling out a distinct group of people as sophists, old comedy seems to use σοφιστής as a derogatory epithet applied to a broad category of intellectuals. The sophists “are presented more as an example of a familiar social nuisance (or in the case of Sokrates as an example of unworldly folly) than as a new and sinister corrupting force.” 
In Isocrates there is a distinction between what the sophists say and what they do: their official position is to dismiss the value of money—presumably in line with dominant social norms—while privately pursuing monetary gains. What upsets Isocrates is that they deviate from their publicly stated position. In contrast to Plato’s one-dimensional picture of sophistic greed, Isocrates acknowledges two points about teaching for pay: one that the sophists themselves publicly promote (disregard for money), and one that attracts Isocrates’ censure (greed). Far from openly announcing their fees, the Isocratean sophists are careful, at least rhetorically, not to violate the propriety of the social norms by presenting themselves as engaged in money-grabbing practices. They do not publicly endorse the practice of offering instruction for money, nor do they describe their relationship with students as an economic rapport between producer and consumer.
In Against the Sophists, Isocrates appears to be using the sophists as foil for the articulation of his own intellectual position. He lumps them together as an amorphous group that he can attack with impunity. This practice resembles closely Carey’s description of old comedy’s utilization of the label sophist in respect to a broad type of sophoi as “an example of a familiar social nuisance”  —an indistinct group of people onto whom a number of unattractive qualities can be projected and subsequently criticized.
Money and Sophia
Building on Grube, Paul Roth has explored the intellectual indebtedness of fifth- and fourth-century seers to their surrounding intellectual environment, and he has persuasively argued for strong overlaps.  Just like sophists, then, seers are represented as practitioners of wisdom eager to sell their sophia to anyone interested in paying for it, and their avarice is viciously criticized. The treatment of the Theban seer Teiresias in tragedy is exemplary of this development—a treatment we will explore next to illuminate the typological characteristics of the censure against seers.