Semantic theories claim that when a sentence contains two epistemic modals,
one modal is within the scope of the other. However, it is possible that,
in casual conversation, the scope of nested modals may only be partially
processed, and thus, changing the order of the modals might not change
interlocutors’ interpretations. This study used a probability judgment test to
investigate people’s interpretations of nested epistemic expressions.
Results showed that although nested modals yielded probability estimates
between values for modals presented individually, the effect of word order
was not observed, thus not supporting the scope account of the nested
epistemic expressions.