Proof for the necessity of supreme leadership of the Imam is that it is a divine favor and it is a necessary rational principle [that reason commands its necessity]. For example: knowing that God exists, a principle, which no duty-bound (Mukallaf) can be without. Don’t you see that it is evident that when a fallible group of people are without an awe-inspiring and venerable leader, who would stop the enemy, reprimand the criminal, seize the hand of the counterfeiter, and defend the weakling against the strong, mischief occurs, deceptions spread, debauchery increases and propriety becomes a rarity? And when they have a leader with these qualities, the situation is reversed, with integrity expanding and encompassing and mischief becoming uncommon and rare? This is very obvious and anyone with common sense would agree to it rendering anyone who disputes it unworthy of conversation. We have fully responded to any imaginable query with this regard in Talkhis Shafi and Sharh Jamal and will not lengthen the inquiry by mentioning them here.
