This is the second title concept of a 1947 book which describes a class of sentences called “state-descriptions” that contain either an atomic sentence or its negations. The letter K denotes a logical axiom that distributes this property. In the Barcan formula, this property is applied (15[1])to statements containing the existential and universal quantifiers. (-5[1])This property is the last word in the title of a book that uses “H2O is water” as an example (15[1])of an a (*) posteriori statement with this property, which is denoted with a box-shaped operator. This is the second concept in the title of a book that discusses how an “initial baptism” fixes (10[1])a referent, thus creating rigid designators. Both this property and (10[1])sufficiency hold for biconditional (10[2])statements. For 10 points, a Saul Kripke (“KRIHP-kee”) book is titled Naming and what word, (10[2])which describes statements that must be true? ■END■