In this paper I propose to inquire what estimate of the tragic poet Agathon may be derived from the plays of Aristophanes; to consider how far the view thus inferred can be confirmed from independent sources of information; and to touch lightly upon the general question of literary criticism in Aristophanes.Aristophanes possesses so many higher titles to fame that it is easy to forget that he may from one point of view be regarded as the earliest of literary critics, and that to his poems, either directly, or indirectly through the scholiasts, we owe much of our knowledge of certain aspects of Greek literary history. It is true that, as a poet-critic, he confines his criticisms almost entirely to the poets. But among these he refers by name to some forty or fifty,—one or two of them epic poets, a few lyric, a larger number writers of comedy, and a still larger number writers of tragedy.