A critique and review of Massoud Ismaili's book "The Essence of Mystical Knowledge" examines how the author investigates the nature of mystical knowledge within both Islamic and Western contexts using a comparative approach. The book is judged largely successful in the field of the philosophy of mysticism, though it contains some formal and material shortcomings.
A review of the book "The Single Experience" finds that it fails to engage with the theoretical foundations of wisdom and the key theories of constructivism and philosophia perennis, which are directly relevant to its subject. The book also makes incorrect claims about religions, such as denying the unity of existence in Judaism. Despite these shortcomings, the book's focus on a single mystical experience may help extend the topic and foster convergence between religions and their followers, potentially deepening religious beliefs.
Rudolf Otto's book Mysticism, East and West is a landmark in comparative mysticism, arguing that mysticism is fundamentally a kinship between Eastern and Western traditions. Otto uses the concept of the "Numinous" or Sacred to bridge historical and geographical divides between religions. First published in 1926, the work compares the Hindu mystic Shankara, representing Eastern mysticism, with the Christian mystic Eckhart, representing Western mysticism. Otto seeks to provide a model for understanding religious truth and comparing religious thinkers, presenting mysticism as a phenomenon that is inherently East-West in nature, building on ideas first explored in his 1923 book The Idea of the Holy.