I had a dream, actually, the night before the decision had to be
made. I dreamed that I was in the desert and it was night. I needed some
place to lie down, some shelter, and came upon this lean-to made of
posts angled up against some sort of wall or cliff face. And over the
posts there were skins or some sort of covering. I crept in underneath
this to sleep for the night and then in the next frame of the dream it’s
broad morning, sunlight, the cliff face has disappeared, the lean-to is
gone, I’m out in the open. What I had taken to be a solid wall had
actually been the side of a liner docked in the Suez Canal and during
the night the liner had moved on. So I took this to mean nothing is
permanent, that I should go with it — although I’m sure there are other
ways of interpreting it.
Seamus Heaney, Paris Review interview