Octogenarian pulitzer winner still at work

He is 86 years old, his eyesight is failing and much of his recent work reads like a man saying goodbye.

But W.S. Merwin continues to write poems; he cannot help himself.

"I wrote the last one about 10 days ago, it doesn't stop, and I don't know where it comes from," says Merwin, a two-time Pulitzer Prize winner and former US poet laureate widely regarded as among the greatest poets of the past half-century.