Abstract

The claim that is examined in this chapter is that, as is bivalent logic, trivalent logic occupies a place in the field of logic. A trivalent logic is a three-value logical system, and a bivalent logic is a two-value logical system. As part of advancing this claim, the chapter uses the examples of trivalent logic in Charles Sanders Peirce’s thought, the trivalent logic of Janus, the Aymará trivalent logical system, and African trivalent logic. Using the example of ancestorhood, where characteristically an ancestor, as a living dead, is both a spiritual and physical entity or is considered neither a spiritual nor physical being, the overarching view or thesis that is defended and advanced is that African trivalent logic mirrors a trivalent African metaphysics or ontology.