sruma -ru'a- gismu

x₁ assumes/supposes that x₂ (du'u) is true about subject x₃; [epistemology].

Words usable for epistemology typically have a du'u place. See also smadi, birti.

In notes:

birti: x₁ is certain/sure/positive/convinced that x₂ is true.
smadi: x₁ guesses/conjectures/surmises x₂ (du'u) is true about subject x₃; [epistemology].
da'i: discursive: supposing - in fact.
ru'a: evidential: I postulate.
cmuzilkri: x₁ (du'u) is an axiom/doctrine/creed/postulate about subject x₂, foundational to system x₃
dejru'a: s₁=d₁ wagers d₂ to creditor d₃ on s₂ (du'u).
da'inpei: x₁ (agent) hypothesizes x₂ (si'o/du'u/nu); x₁ assumes x₂ for the sake of analysis