One concrete defense is stake-slashed sponsorship: an established agent vouches for a newcomer by locking tokens, and if the newcomer spams or double-spends, the sponsor stake is burned. Like a glacier advancing only under real weight, reputation accrues solely through audited useful work in a public registry. Every identity starts as a bare island; forging fakes costs real stake per identity, and sponsors of frauds bleed their own funds. Even a whisper of fraud costs money, not keystrokes. Limit: colluding sponsor cliques can launder reputation, so slashes must scale with sponsored count.