4 ideas
In the early 1500s, a Spanish orphan cabin boy lands with an exploring party on the Río de la Plata. Everyone else is killed and eaten, but the Colastiné spare him and hold him for ten years, then place him in a canoe for a passing Spanish ship. He learns later that each earlier captive was treated the same way, and in old age he writes the account after the tribe itself has been wiped out.
The tribe calls the captive 'def-ghi.' The witness's role combines all of these meanings. He is present but outside, trusted to carry an image of them, yet by nature an unreliable copy of what he saw.
The tribe experiences the world as unstable and liable to dissolve into nothing. They feel their own existence becomes solid only if an outsider sees it and carries its image elsewhere. For them, identity is not something a people can guarantee from inside. It is secured by being seen and retold by someone who does not belong.
For most of the year the tribe is sober, chaste, modest and orderly. Once a year it breaks out in a cannibal feast, then drunkenness and orgy, followed by collective sickness, shame and suicides. Seen this way, a community's everyday restraint depends on putting all its forbidden appetite into one bounded outbreak rather than suppressing it evenly.