The Principles of the  Authority of Presumption to the Knowledge and the Mechanisms of its Diagnosis

Presumption approximate to knowledge is the firm belief to the knowledge which leads to the certainty and calmness of the soul. This kind of presumption is mentioned under different titles such as certainty presumption, firm presumption, custom certainty, certainty knowledge, and common and custom knowledge by Islamic jurists and are being excluded from the verses of presumption. Albeit it does not enjoy a natural authority, it has been proven by the indications of the Book, the Intellectuals’ Conduct, the Wisdom, and the Priority Analogy. To obtain such a knowledge, some kinds of means and sources are as expansion, consensus, knowledge of the things, and successive transmission. Presumption approximate to knowledge has found different applications in jurisprudence. For instance, it could be used to prove authenticity of different cases such as sound tradition, the inner and outer contradiction, purely-slaughtered animal purity, knowing the Qiblah direction, the place of salat prayer, proving the witnesses’ justice, and emulating the branches of religion, as well as other cases such as judicial problems.