In Percy Bysshe Shelley’s essay “A Defence of Poetry,” tradition seems to be viewed as an important precedent or example. It serves as a guide that helps Shelley think about the present.
For Shelly, the traditional dramas of Greece are important. When he speaks about the traditional Athenian drama, he praises how music, action, painting, dancing, and other elements all came together to create “the highest idealism of passion and power.”
He contrasts that tradition with the modern stage. Shelley doesn’t seem to have a high opinion for the theater of his time (the early 1800s). There isn’t a unity of elements. Nowadays, for Shelley, the plays produce a “partial and inharmonious effect.”
Of course, Shelley is able to reach these conclusions via tradition. By knowing what plays were like before his time, he has a better understanding of the history of theater. From that understanding, he can offer more informed critiques and judgments. It doesn’t necessarily make them right, but it does make them credible. His inclusion of tradition demonstrates that he’s a scholarly, learned critic.
The same goes for poetry. Shelley’s knowledge of poetry’s history—whether it be poetry in Charles II’s England or the poetry in the doctrines of Jesus Christ—helps him figure out how his contemporaries can continue the ideal poetic tradition.
Tradition also helps him sort through how the poet’s role in society has changed. According to Shelley, past poets like Dante and Milton were “deeply penetrated with the ancient religion of the civilized world.” Now, according to Shelley, poets are relegated to a secondary status. They’re being asked to “resign the civic crown to reasoners and mechanists.”
Without tradition, Shelley probably wouldn’t be aware of times where poets were much more valued and exalted. Yet his knowledge of tradition and the past make him aware. It makes his points legitimate and worthy of discussion.