AGAINST THE BLUE

They didin't seem like individual birds, or even individual dots of black against the blue; it was the flock itself that was the individual. It was like a single piece of cloth, cut in a very complicated way that let it swing through itself and double over and stretch and fold in three dimensions without ever tangling, turning itself inside out elegantly waving and crossing through and falling and rising and falling again.
(Philip Pullman | Lyra's Oxford)