Dead languages present a case where the original language community no longer exists. This results in a language for which the evidence is limited by the paucity of surviving texts and in which no new linguistic uses can be generated. Ludwig Wittgenstein argued that the meaning of language is simply its use by a language community. On this view a dead language is coextensive with the existing corpus, with the linguistic dynamic provided by the community of readers. Donald Davidson argued that the meaning of language is not conventional, but rather is discovered in a dynamic process of "passing theories" generated by the speaker and listener. On this view a dead language is incomplete, because such dynamic theories can only be negotiated by participating in a living language community and are thus not captured by the extant corpus. We agree with Davidson's view of theories of meaning and conclude that our interpretations of dead languages will suffer epistemological underdetermination that removes any guarantee that they reflect the meanings as heard by the original language community.