Published in 1969, Knowing the Spirit (Ma'refat ol-Rûh) reads like a classic philosophical treatise. Resurrecting the canonical form of the philosophical-theological discussion, this work may at first seem unique among Ostad Elahi's writings as a purely theoretical text. On closer inspection, it proves to be much more complex. Although it is the product of several years of extensive theological and philosophical research, it is mostly the result of a rigorous practice of the mystical understanding of the soul. Drawing from the discursive and conceptual background of the metaphysical tradition with which he was familiar, one which links Neoplatonism to Avicenna and Mollâ Sadrâ, Ostad sets forth the findings of his personal research. Beneath the impeccable constructions of proofs, refutations, and counter-refutations, one can decipher the marks of an original knowledge acquired through personal experience, a firsthand account as irrevocable as the philosopher's arguments. This inner vision of truths, referred to in the Islamic tradition as "kashf," is an intuitive and concrete perception of intelligible or invisible realities. Thus, Knowing the Spirit allows two different readings: at a philosophical level, one follows the chains of reasoning and the analytic exposition of concepts; at a deeper level, one touches on revelation and spiritual knowledge. At the first level, the network of arguments laid out by the author implicitly points to the limits of a purely conceptual philosophical discourse (positions refute one another), while at the second level the actual process of the soul's perfection sets forth both the condition for and the very object of spiritual discourse.