Theory of Forms

Read this description of Plato's theory of the forms. What does Plato mean by "forms"?; How does this relate to justice? What does the ideal state have to do with justice?

The English word "form" may be used to translate two distinct concepts that concerned Plato – the outward "form" or appearance of something, and "Form" in a new, technical nature, that never

...assumes a form like that of any of the things which enter into her; ... But the forms which enter into and go out of her are the likenesses of real existences modelled after their patterns in a wonderful and inexplicable manner....

The objects that are seen, according to Plato, are not real, but literally mimic the real Forms. In the Allegory of the Cave expressed in Republic, the things that are ordinarily perceived in the world are characterized as shadows of the real things, which are not perceived directly. That which the observer understands when he views the world mimics the archetypes of the many types and properties (that is, of universals) of things observed.

In the Allegory of the Cave, the objects that are seen are not real, according to Plato, but literally mimic the real Forms.