diagraming the forest, bas-relief

Pentheus pursued by the Maenads.

In the background, the civilized world, things are black and white, very distinct. It is a world of abstract distinctions.

In the forest, distinctions, between all things-- sacred and profane, culture and nature, human and animal-- become indistinct.

This situation in the forest reveals how the Maenads are no longer completely human in their context/state, but also how Pentheus, having wandering into the forest, is not completely human himself, or how he is reminded of his disturbing origins. This is exaggerated by the chiaroscuro, the lack of distinction, or coexistence of, black and white-- the Maeneds are dark (representing the darkness of the forest and primordial origins), barely lit by light. Pentheus runs toward the light of civilization. He is almost illuminated, but not entirely. And we know he's not going to make it.