A ledger is a list of keys and values. A transaction is a mutation of the ledger in which some value is reassigned to new keys.
All valid proposals are immediately added to a priority queue, which is digested at a specific pace, such as one thousand per second. The prioritization is the order which equitably distributes this bandwidth to each unit of currency—the slowest-moving money deserves to be moved first.
Machines become peers using a ledger as a self-mutating communication protocol, in which they perpetually stream to one another each mutation implemented in real time. There will be subjectivity in the order in which each machine apprehends messages, but each can infer an objective chronology from the processing stream, knowing that each message will have delayed the communication of all other messages of lesser priority.
The realistic limits of clock accuracy and network communication speed define the boundaries of unanimous interpretation; a message should only refer to context established by at least a few seconds. A dubious message betrays itself by tempting these boundaries, provoking a proof-of-stake condemnation in which it is silenced to preserve network consensus by having its monetary source deleted.
The result is a proofless cryptocurrency: all transactions are established by no proof other than their own existence, requiring no consent other than from the payer and payee, with no delay, and no cost.