A weary wanderer lies down on a riverbank, and the river stands up. In the Aeneid (composed c. 29–19 BCE), the Trojan hero, his heart worn by war, sleeps among the poplars until "The River-Father, genius of that place" — its indwelling spirit — rises to him: "Old Tiberinus visibly uprose", an old man in "A cloak of gray-green lawn he wore, his hair / O'erhung with wreath of reeds". He greets the sleeper as "Seed of the gods", foretells the white sow that will mark the site of the coming city, names himself — "I am the copious flood", the "cerulean stream / Of Tiber" — and, his counsel given, "So spake the river-god, and sank from view". The water is not a setting but a speaker: a god with a face, a garment, and a voice, who withdraws into his own current once the message is delivered.

The record keeps a second river-god half a world east. In Myths & Legends of China (published 1922), a drowned official, Ch'ên Kuang-jui, is saved because the carp he once spared was in truth "Lung Wang, the God of the River", the river's lord "going through his kingdom in that guise" when he was caught in a net. Remembering the kindness, "Lung Wang had saved him", made him an officer of his court, and on the day the man's murder is avenged the god sends his body back: it "revived, and came out full of life and health". There the Tiber is prophet and host; here the river-god is sovereign and rescuer, a court beneath the water with power over life. Both are the same intuition — that a moving water has a will, a rank, and a memory.

If a river can rise, speak, and lie down again, where does the god end and the water begin?