In his book on the commentary of Sura Kawthar, Sayyid Muhammad 'Ali acknowledged the existence of the Hidden Imam and wrote about the signs and indications of that existence. Thus, for instance, he writes:
There is no doubt about the existence of the Hidden Imam. The reason is that if he did not exist no one else would have existed. As such, this matter is as clear as the sun in the sky. The problem is that the necessary corollary of doubt in his existence is doubt in God's power. Anyone who doubts the existence of God is a disbeliever. . . . As for the Muslims and the believers among the followers of the Twelve Imams, the Imamiyya, the period of his birth is proven (may my spirit and the spirit of all those in the realm of the spiritual beings -- malakut -- be a sacrifice for his excellency!). Moreover, his short occultation and the miracles that took place in those days, as well as the signs that were given to his deputies, are also proven beyond any doubt. . . . He (the twelfth Imam) is a righteous offspring. His patronymic is Abu al-Qasim. He is the one invested with God's command (al-qa'im bi-amr allah), the proof of God's existence for God's creatures, the remaining one (baqiyyat allah) among the servants of God, the Mahdi who will guide people to the mysterious matters. But I do not like to mention his name, except the way the Imam ['Askari] has mentioned it, that is, mim, ha, mim, da. There are texts in this regard, directly received from the [twelfth] Imam (peace be upon him). The Imam himself has written the note in which he says: "God's curse be upon the one who mentions me by my name in public.". . . The Master of the Age (wali 'asr) will have two [forms of] occultation. During the lesser occultation, he had trustworthy and intimate deputies and agents. The period of the lesser occultation lasted for seventy four years and some days. The deputies of the respected master (may our spirits be a sacrifice for him!) include: 'Uthman b. Sa'id 'Amri and his son, Muhammad b. 'Uthman, Husayn b. Ruh, and 'Ali b. Muhammad Samarri.
In another place in the same book he writes about his own experience of having seen the twelfth Imam in Mecca:
One day I was busy praying in the holy mosque of Mecca, on the side of the Yamani pillar [of the Ka'ba]. I noticed a well built and good looking young man who was deeply involved in performing the circumambulation (tawaf). He had a white turban on his head and a woolen cloak on his shoulder. He was with the merchants' group from Fars. There was no more than a few steps of distance between us. All of a sudden a thought came to my mind that he could be the Master of the Command (sahib al-amr). But I was embarrassed to go closer to him. When I finished my prayers I did not find him. Nevertheless, I am not so sure that he was the Master of the Command.
