Socrates goes on to express his desire to understand further the nature of this persuasion by rhetoric. He maintains that many professions, such as teaching, also involve some form of persuasion. In order for a student of any trade or profession to believe, or become convinced of, or learn the practice in question, their teacher must persuade them somehow through reason that the proposed information is knowledge (justified true belief). Therefore a teacher of math must persuade his students that a given equation is true through examples of its operation, and a purveyor of philosophy such as Plato must persuade recipients of his ideas (Socrates's listeners) of the truth of his ideas through writing and dialogue. From this construction, it follows that other skills than rhetoric involve the practice of persuasion. Gorgias predictably concedes this point as well, and then he states that rhetorical persuasion concerns itself with right and wrong.
At this point Socrates digresses somewhat into an exploration of knowledge and belief. Essentially, he argues that belief may be true or false, but knowledge by definition must be true, or else it is not knowledge. Rather than questioning the metaphysical nature of this declaration, he simply states it as a fundamental aspect of knowing, beyond argument. Correspondingly, one type of persuasion produces belief without knowledge (false belief), while another produces knowledge (true belief). Now, according to Gorgias, rhetoric's territory lies mainly in the courtroom. Gorgias also, however, agrees that the kind of conviction about right and wrong created in the courtroom or at any other gatherings "is persuasive but not instructive about right and wrong."
Gorgias moreover maintains that rhetorical oration is capable of convincing a crowd on almost any subject, though it is not the expertise of any one particular pursuit other than the general ability to persuade. In fact, no expert in any given field would be more convincing on the subject of their profession in front of a crowd than an rhetorician with no such applied ability.
This point both embodies the nature of rhetoric and serves as a liftoff point for Socrates's crucial distinction between art and flattery. Socrates declares that claim provides proof that the ignorant is more convincing among the ignorant (a crowd) than among the expert. This is the case for all other arts, as well. Herein lies the crucial difference: whereas a routine such as rhetoric appeals to an excitation of pleasure in order to create the impression of good and therefore appear desirable, the true arts forsake all (including quick gratification of the mind and body) in favor of the good. Thus, Socrates says, rhetoric is "not an art, but the occupation of a shrewd and enterprising spirit, and of one naturally skilled in its dealings with men, and in sum and substance I call it 'flattery.'" This distinction furthermore applies to all arts and routines, such as gymnastics, medicine, legislation, and justice. Thus, "Sophistic is to legislation what beautification is to gymnastics, and rhetoric is to justice what cookery is to medicine." Arts without exception are rational and good, while routines aim at the pleasant and ignore the good.
This section is absolutely vital to Plato's project within Gorgias. He will ultimately go on (through the mouthpiece of Socrates) to base most of his arguments against his contemporary opponents on this confusion, which itself ends up equivalent to the failure to distinguish the good from the pleasant (see the following sections). In this way, every mistaken attribution of proper power, justice, temperance, and overall good living by Socrates's fellow Athenians hinges upon errors similar to those causing a conflation of arts with routines. Plato's structuring here of Socrates's argument in this way takes on new importance in terms of the overall direction of Gorgias. In addition, further significance for this section results from its reflection of the true sentiments and beliefs of Athenians contemporary to both Socrates and Plato (and ultimately responsible for Socrates's trial and death). The claims contained herein take on a new meaning in light of this perspective. And, somewhat surprising in such a passionate text, its force hinges upon a rather formal logical distinction between knowledge and belief rooted in its implicit definition of knowledge as (justified) true belief. In other words, false knowledge is not knowledge at all, but rather a mistaken belief.
It is also noteworthy that Plato establishes the crucial distinction here between art and routine on grounds of mob ignorance. Moreover, Gorgias readily agrees with the proposition. The basic thrust of this claim is that within a crowd, an average person (as most people are, since this is why it is 'average') is apt to listen to others (including the rest of the crowd as well as any one authoritative speaker) only in a cursory way when deciding what to think, do and believe in any given situation or decision (they even listen to themselves in a cursory way). This fundamental irrationality comes as opposed to a use of reasoned introspection and thought employed in order to gain insight into the truth of any given situation, which truth itself will dictate its own actions for the circumstances in consideration. One consequently should note that exactly this existence of public and courtroom ignorance was responsible for the wrongful execution of Socrates, and it threatened to destroy Athenian society when the dialogue was written. In fact, one legitimately could argue that this ignorance of the crowd directly causes Plato to create such a treatment of the issue as the Gorgias text, so that the problem may be remedied before all was lost.
With such a treatment of true versus false art comes Plato's first, if as of yet unsubstantiated, hint that the good is different from the pleasant. For, while the good truly is good, the pleasant falsely flatters in order to create an incorrect belief of good. The value of art is real, while that of routine is apparent. Without question this is an impressively simple distinction, and yet its impact could not be more far-reaching. As Plato portrays the situation (through his mouthpiece Socrates), the ever-growing corruption of his contemporary society takes root entirely in the mistaken attribution of good to the pleasant, regardless of specific art or flattery. By exposing this fallacy, as Socrates does through the remainder of the dialogue, Plato attempts to spark massive and (as he saw it) necessary reform.