>>29
Coincidentia oppositorum, a common concept in pagan philosophies.
See also Pliny the Elder's Natural History, in which an eagle and snake fight to the death and become entangled (a two-headed eagle).
>Nor is one Enemy enough for the Eagle ; but her Fight with the Dragon is more sharp and much more dangerous, although it is in the Air. The Dragon, out of a greedy Desire to do Mischief, watcheth to destroy the Eggs of the Eagle ; but the Eagle again for this, wherever she can see him, catcheth him up. The Dragon, with many Folds windeth about his Wings, and so entangleth them that they fall down both together.