In the language of mathematics and logic there are essentially two types of statements. There are basic propositions (abbreviated here by lower-case, italicized letters, e.g., p, q, etc.), like "the triangle ABC is equilateral," or "the integer a is...

Property of logical connectives, whose in variant meaning guarantees that the whole meaning of complex sentences can be represented as a function of the truth values of the component clauses. (=also extension, propositional...

In mathematical logic, a truth function is a function from a set of truth-values to truth-values. Classically the domain and range of a truth function are {truth,falsehood}, but generally they may have any number of truth-values, including an infinity...