Written in answer to his friend Thomas Love Peacock’s essay ‘The Four Ages of Poetry’ (1820), this begins as a treatise of ‘accurate philosophy’ but, aptly, evolves into declamatory prose laden with imaginative imagery.
Best known for its last line (‘Poets are the unacknowledged legislators of the world.’), this is perhaps its least cogent point, dependent on using ‘poetry’ in its broadest sense, as the essence of everything artistic and spiritual. Shelley sets out, influentially, Romanticism’s critical history of literature and also Romantic opposition to capitalist economists’ increasing introduction of a new ‘calculating’ morality. He had other ideas about ‘utility’.
Related recommendation: Sir Philip Sidney’s ‘An Apology for Poetry’ (or ‘A Defense of Poesie’, written 1579, published 1595)
Themes: The Classics, Artistic Method, Vocation and Celebrity, The role of Art or Artists
Genres: Critical, Lyrical or Poetic, Tract or Treatise