It’s not about underdetermination. Gold’s negative results are sometimes wrongly taken to be an unsurprising reflection of the underdetermination of theories by finite bodies of evidence (Hauser et al. 2002 seem to make this erroneous equation on p. 1577; so do Fodor and Crowther 2002, implicitly—see Scholz and Pullum 2002, 204–206). But the failure of text-identifiability for certain classes of languages is different from underdetermination in a very important way, because there are infinite cl