"A Defence of Poetry '' is an essay by the English poet Percy Bysshe Shelley, written in 1821 and first published posthumously in 1840 in Essays, Letters from Abroad, Translations and Fragments by Edward Moxon in London. It contains Shelley 's famous claim that "poets are the unacknowledged legislators of the world ''.
who described poets as the unacknowledged legislators of mankind
Percy Bysshe Shelley