This in turn may explain the second difference between then and now: the imaginative confidence of poets themselves. Shelley was wrong to think that writing poems like “Queen Mab” or “Prometheus Unbound” would bring revolutionary change to England, but his conviction that they would is what allowed him to write the poems in the first place. Today, poets with a grasp of reality must start from the premise that nothing they write will be much read or have much influence on public discourse. A poetry written under such circumstances may have its own virtues, but they will not be the virtues of the Romantics — conceptual boldness, metaphysical reach, the drive to bring religion and politics themselves under the empire of art. As if in recognition of this fact, poets in our time prefer to imagine themselves not as legislators, but as witnesses — those who look on, powerless to change the world, but sworn at least to tell the truth about it.