The sources of information most obviously open to the student of ancient Greek religion are the Art and the Literature of ancient Greece; and the idea that modern Greece can have any teaching to impart concerning the beliefs of more than two thousand years ago seems seldom to have been entertained. Just as we speak of ancient Greek as a dead language, and too often forget that many of the words and inflexions in popular use at the present day are identical with those of the classical period and even of the Homeric age, while many others, no longer identical, have suffered only a slight modification, so are we apt to think of Greek paganism as a dead religion, and do not enquire whether the beliefs and customs of the modern peasant may not be a direct heritage from his classical forefathers. And yet, if any such heritage exist, there is clearly a fresh source of knowledge open to us, from which to supplement and to correct the lessons of Art and Literature. Art, by its very nature, serves rather as illustration than as proof of any theory of ancient religion. Sculpture has preserved to us the old conceptions of the divine personalities. Vase-paintings record many acts of ritual and scenes of worship. Architectural remains allow us to restore in imagination the grandeur of holy places. But these things are only the externals of religion: they need an interpreter, if we would understand the spirit which informed them: and however able the interpreter, the material with which he deals is so small a remnant of the treasures of ancient art, that from day to day some fresh discovery may subvert his precariously founded theories. Though all would acknowledge how fruitful in religious suggestion the evidence of art has proved when handled by competent critics, none would claim that that evidence either in its scope, which the losses of time have limited, or in its accuracy, which depends upon conjectural interpretation, is a complete or infallible guide to the knowledge of ancient religion.