Plato was extremely devoted in answering the sophists’ skepticism about reason and morality. To do so, he spent more time than any philosopher before him studying knowledge, or epistemology. He realized that to answer the sophists’ skepticism he had to first solve the three main problems that earlier philosophers had left behind; the problems of change, the “one” and the “many”, and the problem between appearance and reality. Plato started where Heraclitus, who said that everything is changing, and Parmenides, who said that nothing ever changes, left off. He said that both philosophers were correct in their assumptions, for they were talking about different types of objects. Heraclitus is correct in terms of the sensible realm; it obviously exists, and is a flux that conforms to the “measures” as he suggested. Parmenides was correct in terms of the intelligible realm. Plato thought that beyond the world of physical objects in space and time is another world that is nonphysical, non-spatial, and non-temporal. He called this the world of ideai, or forms.
These forms are nonphysical, non-spatial, non-temporal objects of thought that are more real than anything else. Whenever we are thinking, according to Plato, what we are thinking about is a form. For example, a triangle drawn on the board in class, no matter how perfect and real it may appear is merely a copy of the form of triangle; a plane figure enclosed by three straight lines. It is like a triangle and looking at it helps us think of the real triangle, but it only relates, or “participates” in Plato’s terms, to its’ true form. This theory applies to the entire sensible realm because everything changes and nothing stays exactly what it is. In the world of forms, however, everything is always what it is and never another thing. Plato believed that because the world of forms is Parmenidean, or eternal and unchanging, it is therefore possible for us to know it.
To explain his theory of forms in depth, Plato used the image of the “divided line”. Take a line and divide it into two unequal parts, one part representing the physical world and one representing the world of forms. Then, subdivide these two parts in the same ratio, creating two sub-parts of the physical world (call them A and B) and two of the world of forms (call them C and D). Plato says let the first, or lowest, section of the physical world (A) stand for images, such as shadows or reflections. Let the second section of the physical world (B) stand for the actual objects that cast these shadows, like trees, humans, or desks. In the world of forms, Plato continues, let the first section (C) stand for the lower forms, or the forms of the objects in section B. The second section in the world of forms, the highest section of all, (D) then stands for the higher forms, or the science of first principles; the knowledge that, if possessed, would prove the basic assumptions of the special sciences.
Plato believed that the nearer we are to the base of the divided line (A), the more conditioned our knowledge is. We can move up the line through dialectic, a process of questions and answer that utilizes hypothesis, criticism, and revision to move nearer to unconditioned knowledge. The higher we climb via this dialectic, the more we rid ourselves of conditions and the better we grasp the knowledge of the non-material abstract forms (D). According to Plato, these are the forms that possess the highest and most fundamental kind of reality.
2. a) How does the Form Man explain the existence of the many individual men?...