ABSTRACT
Metaphysics, very generally considered, asks: what things are real, and in what does their reality consist? Epistemology asks: what can we know, and how do we know it? The two questions may be kept distinct from one another, as they largely have been in philosophy since Descartes, but in the Republic Plato interweaves questions of reality with questions of knowledge, on the grounds that the kind of reality or being an object has corresponds to the mode of cognition one can have of it. This grand unification of all philosophical inquiries is typical of the middle section of the Republic, and is one reason for its philosophical importance, though trying to make the whole system work leads Plato into some tangles.
