There are various ways of distinguishing superficial from profound art. Beauty, sincerity, reality are the usual catchwords of differentiation, the only trouble with them being that, while apparently everybody knows vaguely what they mean, nobody ever has exactly and completely defined them. Another test, not quite so general, is to ask whether the artist has irony. If he has genuine irony, he must be approached with utmost respect; if he does not have it, or has only the seeming of it, he may be interesting in a dozen different ways, but he cannot be a really serious interpreter of human life. If other qualifies were equal, Shakespeare would still be superior to Jonson by the test of irony. In a similar way, irony alone would differentiate the sonnets of Shakespeare from the sonnets of a hundred technically capable but unironical contemporaries. In modern times, it might be a mark to separate a play by Eugene O'Neill from any typical Broadway success; or Thomas Hardy from Harold Bell Wright; or Edith Wharton and Louis Bromfield from the glib and plausible Edna Ferber.
Is irony easier to define than the other qualities mentioned? Yes, because ir is an attitude determining the artist's approach to his material. On the negative side, it means a refusal to simplify too readily; it declines the narcotic lull of easy philosophies; it will not put on ready-made garments of meaning. On the positive side, it is a conviction that the apparent unity of life is based on diversity and that life is essentially dualistic, with evil and good continually merging, changing places, as well as standing opposed. Irony sees contradictions; the animal as well as the god in man; confusion as well as a moral order; discords