Fuzzy Types and Their Lattices
Fuzzy sets and fuzzy logic is an essential approach to
uncertain and vague information representation and reasoning.
This paper is focused on uncertainty about types of
objects and reasoning with it. A fuzzy type is formulated as
a pair of a basic type and a truth-value, where a basic type
can be crisp or vague (in the intuitive sense). A structure
for a class of truth-value lattices is proposed for this con
struction. Then, fuzzy type lattices are developed with the
fuzzy sub-type partial order satisfying intuition, and fuzzy
type intersection and union operations. The result forms a
basis for development of an order-sorted fuzzy logic system.