In the final, painful months of his life, unable to write and separated from the woman he loved, Keats lamented that he was living a "posthumous existence" - that is, he felt dead already. Ironically, Keats' posthumous life has turned out to be longer and more illustrious than the one he had on earth. Though he'd published just a handful of poems by the time he died in 1821 at the age of 25, his work establishes him as a natural talent and one of the stars of English Romantic literature. We can only imagine the heights his talent would have reached had he lived.
Keats' dramatic life seems like the subject of a Romantic poem, which in fact it was. (Percy Bysshe Shelley, who died just one year later at the age of 29, composed the elegy Adonais upon his friend's death.) He was abandoned, orphaned, mistreated by a wily guardian. Just when it seemed like Keats' life was coming together - his poetry was getting decent reviews, he was set to marry the woman he loved - he was taken down by tuberculosis, the disease that killed his mother and brother. Keats was well aware of the tragic quality of his life - in fact, he could be a little self-pitying - but there's no denying that his own painful experiences contributed to the poignancy of his poems, and to his unparalleled powers of perception.