Understanding the basics of the validity of the appropriate rule and the obstacle

“Appropriate rule and obstacle”, although it is more or less among the evidences of rulings, has been neglected and has not been addressed by some fundamentalists and jurists, and even in this category, “the appropriate rule and obstacle” has not been mentioned as a rule, but has been examined in the context of the issues that are mainly raised in the discussion of istishab. The main question of the current research is whether the rule of “Appropriate rule and obstacle” is valid and what are the evidences of its validity? Therefore, the present article intends to examine and analyze the authority of “the appropriate rule and the obstacle” and the rule of thumb. According to the findings of the research, the appropriate has an independent status and whenever it is said that the appropriate is achieved, that is, it is proven by its independent nature and will undoubtedly have its own requirement, but sometimes something prevents the proper effect, not prevents the proper effect. On the other hand, the obstacle is not always conditional for the proper effect, but it has an effect as an annoyance and an incident outside the proper status, but the condition of the appropriate requirement is not non-obstruction. For the legitimacy of this rule, important arguments indicate that the non-authority of the rule can not be simply stated, but on the contrary, it has been considered as a rule used by jurists and because it is more valuable than practical principles. Therefore, it should be addressed as a jurisprudential rule.