In the fourth and last volume of En Islam Iranien - the summa of his philosophical thought, his research and his work in hermeneutics - Corbin finally has the opportunity to show how the most important spiritual and philosophical currents of the esoteric tradition shī-'ita have been kept alive in Iran, even in the centuries which, in the West, correspond to the modern and contemporary age. In Isfahan, the capital of the new Safavid empire, starting from the 16th century, Shī-’ism ran the risk of becoming a domesticated religion devoid of originality in its schools of thought. Figures like Qāzī Sa'īd Qommī and Mollā Sadrā Shīrāzī, however, have not only kept their spiritual strength alive, but have renewed it with deeply original works and philosophical systems. Even more heartfelt and empathic is the Corbiniian reconstruction of the shaykhī school, which from the eighteenth century up to years not too distant from ours presented great spiritual figures and put the teachings of the  Imam back at the center. Not surprisingly, the great fresco of Shi'ita Iran is terminated by Corbin with a chapter dedicated to the great mystery, and principle of hope, which nourishes the Shi'ita religious consciousness: the expectation of the Twelfth Imām, the Imām which for centuries has hidden himself to return in the time of the resurrection, but which has never ceased to appear in the eyes and in the heart of those who are able to see it, again. The volume contains the analytical index of all four volumes.