∀UNITY: A Theory of General UNITY

UNITY is a simple programming logic to reason about distributed systems. It is especially attractive because of its elegant axiomatical style. Since its power is limited, people introduce variants to extends it with various new functionalities. However, in the axiomatical style it is easy to make a mistake: a seemingly very logical new inference rule may turn out to be unsound. Formal verification is often necessary, but it is a time consuming task. ∀UNITYis a generalization of UNITY. It provides the same set of inference rules, but they are now derived from much more primitive (weaker) rules. ∀UNITYis provided as a HOL (a theorem prover) library, with all its derived rules mechanically verified. Using ∀UNITYa sound and complete UNITY variant (instance) can be quickly created by showing that the instance upholds ∀UNITYprimitive rules. Moreover, all theories one subsequently derives from ∀UNITYwill be valid for all ∀UNITYinstances.