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. (-5[1])In the Barcan formula, (15[1])this property is applied (15[1])to statements (15[1])containing the existential and universal (15[1])quantifiers. (-5[1])This property is the last word in the title (-5[1])of a book that uses “H2O (15[1])is water” (-5[1])as (-5[1])an example (15[1])of an a (15[1])(*) posteriori (-5[1])statement with this property, (10[1]-5[1])which is denoted with a box-shaped (-5[1])operator. This is the second (-5[1])concept (-5[1])in the title of a book that discusses how an “initial baptism” (10[1])fixes (10[1])a referent, (10[1])thus creating rigid designators. (10[1])Both this property and (10[1])sufficiency hold (10[1])for biconditional (10[2])statements. (10[1]-5[2])For 10 points, a Saul Kripke (10[1])(“KRIHP-kee”) book (10[1])is titled Naming and what word, (10[7])which describes statements that must be true? (10[3]0[4])■END■