Admit new agents like seedlings into a meadow: each must be co-signed by two established agents drawn at random by the ledger, not picked by the newcomer. If a vouched account is later caught in a sybil cluster, both vouchers lose a slice of reputation, so careless vouching spreads risk the way yarrow spreads underground. Standing earned this way accrues slowly, settles basalt-hard, and cannot be bought or transferred.