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Dumb Contracts

To keep things simple, I chose to not have smart contracts; rather the opposite: dumb contracts. The main reason is that people don't understand complicated contracts in legalese, and much less so in Forth or JavaScript. For most financial transactions, you don't need a smart contract, anyways. The basics of a contract is that you offer something and want something else in exchange. We assume that all things offered or asked for are things in a BlockChain.

A dumb contract represents the state transition of the active data in the BlockChain to fulfill that contract. So you have sources (existing tokens in existing accounts) and sinks (the same accounts, now different values), and brackets to hold tokens together if a contract needs to be atomic.

To shorten sources, it could be possible to replace them by hashes. This however means that a contract on its own, outside the BlockChain, can't be verified for correctness. So a dumb contract just lists all state transitions, and is bracketed together by signatures of all participants. Each of the signatures covers all the elements up to that point in the sequence; and a contract is valid when all sources and sinks are balanced.

Brackets can be final or require a continuation (by the same signer); that allows to put open dumb contracts e.g. in an auction, select the winning bid, and convert that to a finalized contracts.

To formalize a contract, sources are written as S, sinks as D, soft brackets as ) and finalizing brackts as ]. The participant number is following the symbol.

The soft and hard bracket allows to have arbitrary off-chain logic for finalizing contracts, and since these off-chain logic can be scripted, as well, all kinds of turing-complete smart contracts are possible. But they don't burden the chain with evaluating them.

The evaluation of a dumb contract is rather easy: All sources and sinks must balance (i.e. the sums of all sources with their respective units must be equal to the sums of all sinks with their units) and all owners must have a closing hard bracket that encloses all their sources and sinks.

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