Multi-valued logic  Multi-valued logics are logical calculi in
which there are more than two truth values. Traditionally,
logical calculi are two-valued—that is, there are only two
possible truth values (i.e. truth and falsehood) for any
proposition to take. An obvious extension to classical two-
valued logic is an n>2-ary logic. Those most popular in the
literature are three-valued (e.g. Łukasiewicz's and Kleene's)
and infinite-valued (e.g. fuzzy logic) ones.  Relation to
classical logic  Logics are usually systems intended to codify
rules for preserving some semantic property of propositions
across transformations. In classical logic, this property is
"truth." In a valid argument, the truth of the derived
proposition is guaranteed if the premises are jointly true,
because the application of valid steps preserves the property.
However, that property doesn't have to be that of "truth";
instead, it can be some other concept.  Multi-valued logics are
intended to preserve the property of designationhood (or being