Reflections on competence of priority of preventing an evil over securing a benefit as a rule

“Preventing an evil takes priority over securing an interest” and preferring the prohibition side is among discussions raised by Usuli scholars and has been accepted as particular affirmative proposition; the said priority is known among Islamic jurisprudents as “ preventing an evil takes priority over securing a benefit” in whose … is the contrast of evil and benefit. Four interpretations of the said priority may be analyzed, the fourth of which i.e. the contrast of benefit and evil, despite being ignored by Islamic jurisprudents, is qualified to be regulated. Furthermore, in the author’s eyes, the first interpretation of this priority deducted from the rule of reason is also qualified to regulated provided the four following elements are present: type of duty, type of obligation, quantity and quality of probability.