A rational perspective to the question of Imamat and Mahdism in Hadiths The necessity of existence of saviour (review and explanation of the first hadith)

In the words of the innocent and pure Imams, there are clear reasoning that the God had sent down Messengers and Imams for guiding the people. In this way, the obligation of guidance from the part of the God is completed (finished) to his servants. For example, the first citation from the book of 'Al Hojja: Ussul e Kaafi' indicates the four issue of existence of obligation, the specifications of obligation, the necessity of continuance of existence of obligation (even in the era of Khatamiat or final prophet), and the way to identify such an obligation. Reviewing and analysis of this citation indicates that the rational precepts also approve of the necessity of Imamat and its continuance. These precepts are reviewed briefly in this passage.