## A calculus for four-valued sequential logic

- Jan A. Bergstra, Jaco van de Pol
- Theor. Comput. Sci.
- 2011

This note presents a complete axiomatisation for four-valued sequential logic. `Sequential' means that arguments are evaluated from left to right, until an answer can be obtained. Three-valued sequential logic is due to McCarthy [6]. In [1] four truth-values are introduced: true, false, mistake and divergent. Several four-valued logics arise by restricting… (More)