A statement which is rigorously known to be correct. A statement which is not true is called False, although certain statements can be proved to be rigorously Undecidable within the confines of a given set of assumptions and definitions. Regular two-valued Logic allows statements to be only true or False, but Fuzzy Logic treats ``truth'' as a continuum which can have any value between 0 and 1.
See also Alethic, False, Fuzzy Logic, Logic, Truth Table, Undecidable