¬ one-place logical connective read as “not” or as “is not the case” ~ alternative notation for “not” & two-place logical connective read as “and” ˄ and

The language sketched above is better referred to as first-order predicate calculus, as the language only quantifies over (first-order) individuals. A stronger language, second-order predicate calculus, can therefore be constructed…

A relevance logic is motivated by the idea that the premises of a valid argument must be somehow “relevant” to its conclusion. The idea is motivated by the fact that…