Find a source that helps you understand Plato's simile of the line, cave, and sun
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After reading this article I discovered that Plato's law of forms is very much important to understanding his simile of the line, the sun and the cave. In the simile of the line, everything above the divided line is true knowledge and includes the knowledge of the forms. The forms are the concepts or total ideas of thing in the world. The shadows in Plato's allegory of the cave can therefore not be considered true knowledge or knowledge of the forms. These shadows are instead allusions and misrepresentations of reality. Without the knowledge of the forms, you can never know the nature of reality.
The simile of the sun the is mentioned by Plato in order to draw a focus on the idea of goodness or justice. Without the sun the the eye would not be able to see. Without goodness the truths of the intelligible world would be inaccessible.
The simile of the cave is presented in order to draw attention to the importance of Plato's theory of forms. The prisoners in the cave are depended on their sense of sight, which, according to Plato is undependable and not a source of truth or the intelligible world.