 One interesting feature of (F\(_{\textit{cofinal}}\)) is that it appears to be in conflict with a Quine’s thesis of the indeterminacy of translation (taken as a thesis that implies the indeterminacy of meaning). Assume that the set of all observation sentences is cofinal within a reasonably large fragment of a natural language and that the meaning of an observation sentence is identical to its stimulus meaning—(F\(_{\textit{cofinal}}\)) ensures then that the meanings of all the words are determined within our fragment. There has been an attempt to show that (F\(_{\textit{cofinal}}\)) follows from less controversial claims, and perhaps even from claims that Quine himself was committed to; cf. Werning (2004). The heart of Werning’s argument is the Extension Theorem; cf. Theorem 14 in Hodges 2001. The theorem states that a meaning assignment to a cofinal set of expressions that satisfies  (H)  and  (S\(_{\textit{singular}}\))  has a unique extension to a meaning assignment to all expressions that satisfies  (H),  (S\(_{\textit{singular}}\)) as well as its converse (there is a generalized result mentioned in Hodges 2012: 257). The extra assumptions needed to get from the Extension Theorem to a denial of indeterminacy remain questionable; cf. Leitgeb (2005).