Though I maintain that no class of professional Sophists (in the meaning given to that term by the Platonic critics after Plato and Aristotle) ever existed--and though the distinction between the paid and the gratuitous discourser is altogether unworthy to enter into the history of philosophy--yet I am not the less persuaded that the Platonic dialogue Euthydêmus, and the treatise of Aristotle De Sophisticis Elenchis, are very striking and useful compositions. This last-mentioned treatise was composed by Aristotle very much under the stimulus of the Platonic dialogue Euthydêmus, to which it refers several times--and for the purpose of distributing the variety of possible fallacies under a limited number of general heads, each described by its appropriate characteristic, and represented by its illustrative type. Such attempt at arrangement--one of the many valuable contributions of Aristotle to the theory of reasoning--is expressly claimed by him as his own. He takes a just pride in having been the first to introduce system where none had introduced it before.[45] No such system was known to Plato, who (in the Euthydêmus) enumerates a string of fallacies one after another without any project of classifying them, and who presents them as it were in concrete, as applied by certain disputants in an imaginary dialogue. The purpose is, to make these fallacies appear conspicuously in their character of fallacies: a purpose which is assisted by presenting the propounders of them as ridiculous and contemptible. The lively fancy of Plato attaches suitable accessories to Euthydêmus and Dionysodorus. They are old men, who have been all their lives engaged in teaching rhetoric and tactics, but have recently taken to dialectic, and acquired perfect mastery thereof without any trouble--who make extravagant promises--and who as talkers play into each other's hands, making a shuttlecock of the respondent, a modest novice every way unsuitable for such treatment. [Footnote 45: See the last chapter of the treatise De Sophisticis Elenchis.] [Side-note: Aristotle (Soph. Elench.) attempts a classification of fallacies: Plato enumerates them without classification.] Thus different is the Platonic manner, from the Aristotelian manner, of exposing fallacies. But those exhibited in the former appear as members of one or more among the classes framed by the latter. The fallacies which we read in the Euthydêmus are chiefly verbal: but some are verbal, and something beyond. [Side-note: Fallacies of equivocation propounded by the two Sophists in the Euthydêmus.]