Modal Epistemic Logic on Contracts: A Doctrinal Approach

Problems related to the construction of consensus out of distributed knowledge have become actual again under a new perspective with the diffusion of distributed ledger techniques. In particular, when dealing with contracts, different observers must agree that a contract is in a certain state, even if not all transactions performed under the contract are observable by all of them. In this paper, we revisit previous work on algebraic modelling of labelled non-deterministic concurrent processes, which identified an intuitionistic modal/temporal logic associated with a categorical model. We expand this logic with typical epistemic operators in a categorical framework in order to encompass distributed knowledge to speak about transactions and contracts.