Problem solving with Japanese 'beki'

Expressions of prioritizing modality vary within and across languages in the criteria they can encode (rules, goals, or desires) and the directive or expressive speech acts they can perform. Crucial parameters include source of evaluation, endorsement, modal strength, and counterfactuality implicatures. Japanese 'beki' is a prioritizing modal which, unlike the better studied Indo-European modals, lacks epistemic readings and interacts with tense transparently, allowing us to isolate modal and temporal effects of past marking.