a lawful esteslah, the urgent need of islamic jurisprudence

there are different views, about the authenticity of esteshal (masalehe morsalah), among the religious jurisprudences of sunnite and emamieh. each of them has offered arguments possibly in rejecting and proving esteslah, but they took an extreme in their arguments. the present study attempts to prove that esteslah, which had been presented by jurisprudents, in the context of social issues, is definite, general and urgent need of islamic jurisprudence, specially, in responding to governmental issues. there are some sunnite jurisprudents, who consider esteslah as an independent source for finding out and conceptualization of jurisprudence laws. on the other hand, some others, along with a group of imamieh, consider it as a subcategory and reasonable proof of tradition, and what is among imamieh acceptable is that esteslah is a subcategory of reasonable wisdom. this issue is inferior to the basic need of a dynamic jurisprudence for esteslah.