rationale

US /ˌræʃ.əˈnæl/
UK /ˌræʃ.əˈnæl/
1.

lý luận phân tách, phân tách lý lẻ, phân tách suy luận

a set of reasons or a logical basis for a course of action or a particular belief.

:
he explained the rationale behind the change