Tomasello argues that by adopting a more ‘user-friendly’ conception of natural language grammars and by radically expanding one's conception of the language-relevant information available to children learning language, the ‘gap’ exploited by the argument from the poverty of the stimulus — that is, the gap between what we know about language and the data we learn it from — in large part disappears. This gives rise to a third important respect in which Tomasello's theory differs from that o