English polar questions with even may trigger an inference relative to the positive or negative answers. However, only may only trigger an inference relative to the positive answer: it may not scope over negation in the negative answer (Guerzoni 2003:94). Guerzoni (2003) argues that even but not other focus particles can move covertly across the question operator, building on the scope theory of even (e.g., Karttunen and Peters 1979). This analysis suffers from the predictability problem: which properties of even and only are responsible for their scope-taking remains unknown. We propose that (i) even does not resolve a Question under Discussion (QUD) (Roberts 1996 / 2012:a.o.) while only has to, and (ii) a focus particle may take an inquisitive prejacent (Ciardelli et al. 2018) only if it does not need to resolve the QUD.
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