Studying Ghazali's and Khawaja Nasir al-Din Tusi's Views on the Issue of Imamate

Al-Ghazali considered the existence of the Imam necessary to Shari'a reasoning and the consensus of the Ummah and considered it useful for the consistency of religion and the world but did not consider infallibility for the Imam. He believes that we need the Imam only in the affairs of the state and equipping the army and ... that he does not need divine knowledge to perform such tasks. He, like other Sunni followers, considers Imam to be the people's choice and introduces any claim by the Shi'a as irrelevant to the issue of Imamate and non-sequential. In his view, if the news were sequential, we would never have doubted it, while we suspected it. Thus hadiths such as the hadith of Ghadir and  Manzelat merely express respect and friendship between the Prophet (PBUH) and Ali (PBUH), and there is no reason to believe in the Imamate of Ali (PBUH).On the other hand, Khawaja Nasir has taken a stand against this view and considers the existence of the Imam to be obligatory, not on religious reasons, but based on rationality and "rule of grace" he considers it obligatory on God. He also suggests that infallibility is essential for the Imam by presenting numerous rational proofs, also, if he performs evil acts, he should be prevented from doing so, and in this case, the purpose of existence of Imam will be violated and the Imam's position will be lower than other people's; therefore, the imam must be installed by God and his messenger, and this is the Nas. However, It is also unlikely that the Prophet would be silent about such danger according to the manner of the messenger of God.