Although the comparison of the Form of Good to the sun in Plato??™s Republic is comparatively sound in its rhetorical strategies, the basis of the comparison of the Form of Good to the Sun, and thus the whole argument altogether, operates under a premise that is inherently inaccurate. Because of this solecism, Socrates??™s argument is ultimately rendered ineffective, as it cannot stand up to a school of thought less narrow in nature.
Plato??™s Theory of Forms suggests that there is only one Form of Good and that there everything that is good is homogeneously good, a point that is so extreme that it can be almost immediately discarded and deemed ineffective. Furthermore, Plato??™s Theory and, in this excerpt, Socrates??™s argument ultimately do not succeed in explaining what they intend to explain. Upon a close reading of this passage, it is easy to see the flaws in Socrates??™s ideas as he makes this comparison, in view of the fact that his argument relies heavily on assumptions and absolutes. In addition, in his dialog with Glaucon, Socrates bases some of his ideas on logical fallacies, which by and large help in crippling his argument. In this passage, Socrates articulates Plato??™s Theory of the Form of Good under the assumption that all things considered ???good??? are each ???good??? in the same sorts of ways, as well as for the same sorts of reasons. In his dialog with Glaucon, Socrates says, ?????¦that what gives truth to the things known and the power to know to the knower is the Form of the Good,??? which implies that only things that are known to us can be good, when in fact, many other good things that are unknown may also be considered good (508e). For instance, when Socrates struggles to explain to Glaucon exactly what the Form of Good is, he laments the fact that he is ultimately unable to provide a perfect, or even adequate, explanation of such a thing (507a). This admission to Glaucon clearly betrays the fact that Socrates does not have the knowledge required in order to explain The Form of Good.
Following the logic he presents in this piece, the Form of Good cannot actually be good, since only things that are intelligible can be good, and the Form of Good cannot be explained. It is in this way that Socrates??™s argument is weakened, because without precise knowledge of the Forms, the Forms are only a belief; and according to Socrates, ?????¦beliefs without knowledge are shameful and ugly??? (506c). Moreover, although Socrates recognizes that not everyone may agree on a definition of ???good,??? he still asserts that ?????¦the more refined believe [the good] to be knowledge,??? which establishes the false premise on which the foundation of his comparison of the Form of Good to the sun is based on.
Although his comparison very thoroughly describes what Socrates believes the Form of Good to be like, it does nothing to prove the reality of such a thing. The use of metaphor here does not function as evidence for an argument, but rather, a clarification of an abstract theory that has no concrete source in reality. The irony here is that Socrates (or more specifically, his tutee Plato) depends very heavily on sight, and yet he is unable to provide any tangible evidence that the Forms even exist. Unfortunately for his theories, Plato??™s Republic submits to a logical fallacy in which he attempts to appeal to authority by using Socrates as a literary device. Rather than writing a comprehensive summary of his own theories, Plato inserts his own ideas into the character of Socrates in order to make his argument appear more credible.
The character of Glaucon provides more evidence for this fallacy in this section of the Republic, since he serves little other purpose than to agree with Socrates as he pontificates over the Forms. Between lines 507a and 509c of the Republic, Glaucon agrees with Socrates in sixteen out of twenty-five of his responses to the theory of the Form of Good, and disagrees with him in zero. In this excerpt, the presence of Glaucon contributes to another logical fallacy found in this argument: the appeal to the majority.
The idea of this fallacy is that something must be true if a significant number of individuals also subscribe to that view. This appeal to the majority does nothing to help either Socrates??™s argument or Plato??™s Theory of Forms. These two are not the only fallacies in this passage, however. In this selection, Socrates says that ?????¦the Form of the Good is knowledge??¦??? and that ?????¦knowledge is the good,??? which is another fallacy altogether. The petitio principii fallacy is a type of circular argument that generally takes the form of an ???x is true because y is true, and y is true because x is true??? statement, which has a conclusion at the beginning as well as at the end of an assumption (507b; 507e). This inevitably deteriorates an argument because it uses a supposition as evidence for an idea. The use of this fallacy also weakens the comparison of the Form of Good to the sun because the former argument is circular while the analogy of the sun is not, rendering the two things somewhat incomparable.
Despite a meticulous allegory for the Form of Good, Socrates??™s logic is ultimately laden with forged logic and quite a few misleading notions. Socrates begins his comparison of the Form of Good to the sun by asserting that when people ?????¦are turned to things illuminated by the sun, they see clearly??¦ But when [they] focus too much on what is mixed with obscurity??¦knowledge is dimmed??¦and seems bereft of understanding??? (508d). This is a valid in that, certainly, it is easier to see most physical things in this world when there is light; however, the inflexibility of this statement again mitigates the overall basis of the comparison as well as the Theory of Forms in general. For instance, it can easily be argued, in keeping with the metaphor, that a dimmer light source would more greatly awaken a more inquisitive and analytical side of the very same group of people Socrates criticizes for their lack of sophistication. To continue once more with the metaphor, an object that is partially obscured by darkness is just as likely, if not more so, to pique the interest of an onlooker, whose goal might then be to identify and understand the object. The subsequent investigation of this emblematic thing will then inspire introspective thought and is just as likely to lead to knowledge as examining things that are in plain sight. The idea that a person can acquire knowledge only when stimuli are presented to him or her in a very explicit way is not always true, so the metaphor again seems to be lacking in certain respects. Although the idea that the sun provides growth and nourishment for living things is true here, the rest of the metaphor falls short because it cannot be said conclusively that the Good does the same thing for knowledge (509b).
Another way in which this comparison reduces the strength of both Socrates??™s argument and Plato??™s Theory of the Form of Good is that they separate the realm of the forms so drastically from the physical world that it becomes impossible to explain how judgment based on observable phenomena or how perpetual existence can be possible in the material sphere. When Socrates says that ?????¦the good is the intelligible realm in relation to understanding and intelligible things, and the sun is in the visible realm in relation to sight and visible things,??? he compares the physical to the metaphysical, which is notionally unfeasible (506c). In a metaphysical world, the physical world cannot be real, so creating a parallel between these two things merely add another conundrum to the question of the Forms. In Socrates??™s comparison of the Form of Good to the sun, he attempts to use the physical to explain the metaphysical, which once again does not prove whether the Forms actually exist.
Plato also presents his Theory of Forms in such a way that shows the Forms as intangible replicas of physical beings or things but provides no explanation of what the difference between the two of them, only that there is one. Because this analogy yet again reveals the sun and the Form of Good as incomparable, Socrates??™s argument is minimized once again. Despite his best efforts, Plato??™s explanation of the Theory of Forms through the character of Socrates does not quite translate logically in the comparison between the Good and the sun. Between the moderately high instances of absolutes and fallacies, it is hard to accept not only the Socrates??™s comparison but the existence of the Forms as well. Furthermore, while the foundation of the comparison is clearly articulated in the text, the basis for the overarching proposal is not. To conclude, the ideas in the Republic are expressed clearly and appear to have intention, but the lack of evidence from Plato and Socrates inevitably gives rise to more unanswerable questions and brings their arguments to a halt.