 Cases of this nature have of course been familiar for some time, but perhaps it has been less on the radar that the uniqueness proposal creates foundational problems for language acquisition theory. It is something of a basic working hypothesis of acquisition theory that semantical components of language are acquired very early and that pragmatic components are acquired much later (see Chien and Wexler (1990), Thornton and Wexler (2000)). This is not surprising, given that pragmatics can involve sophisticated real world reasoning. However, children’s grasp of definite and indefinite descriptions come late in the acquisition process (around age 9; see Karmiloff-Smith 1979 and Warden 1976)), prompting Wexler (2011), working on hypothesis that descriptions are Russellian, to question the working hypothesis that semantics is fixed early. But an alternative explanation is that uniqueness is a pragmatic phenomenon, thus saving the working hypothesis. In other words, a basic working hypothesis of acquisition theory is preserved if we reject the Russellian story about the distinction between definite and indefinite determiners.