Nondeterminism Is Fine Until It Touches a Balance Sheet A probabilistic system can be perfectly safe in finance under one condition: that the things it consumed and the things it produced can be checked. The worry about handing agents real money usually starts from their nondeterminism, the fact that the same prompt can yield different outputs, and concludes that anything this unpredictable has no place near settlement. The conclusion comes too fast, and it misreads where the risk sits. Nondeterminism is a property of the model's reasoning, and it is entirely tolerable in a drafting assistant, a research tool, or a coding aid, where a person reads the output and a wrong turn costs a little time. Finance differs because the output converts directly into an irreversible transfer, with no one reading it in between. The instinct that follows is to make the model deterministic, to pin it down until it behaves like a calculator, and that fights the wrong battle. The value of an agent is its ability to reason flexibly over messy, changing information, and stripping that out to buy predictability discards the reason for using one. The risk worth removing sits on either side of the reasoning rather than inside it. An agent that reads verifiable data and produces a verifiable result can reason as probabilistically as it likes in the middle, because the inputs are known to be true and the output is known to be the real consequence of the query it ran. Probabilistic thinking becomes underwritable when it is bracketed by facts that are not. Space and Time, the data blockchain securing onchain finance, supplies those brackets. A query returns its result with cryptographic proof that it ran correctly over tamperproof data, so the data going into the agent's reasoning is provable and the result coming out is too. The model stays as flexible as the task needs, while the evidence around it does not move.