D. distinguishes nonreferential or attributive uses of definite descriptions (e.g.'Smith's murderer' in 'Smith's murderer is insane' uttered by somebody who comes upon Smith's body and wants to deduce something about the murderer from the brutal manner of the killing) from referential uses (e.g. 'Smith's murderer' in the same sentence, but now uttered in court to refer to Jones who has been charged with the murder). D. claims that the truth value of what is said is affected differently, depending on the use of the definite description, if the presupposition that something should fit the description fails; moreover, it is said that when a speaker uses a definite description referentially, he may have stated something true or false even if nothing fits the description.