encapsulated in the Sephirot, undergoes countless restrictions, diminutions and veilings, to progressively hide Divinity. In Kabbalah these are called "Tzimtzum" ("Constrictions" - plural "tzimtzumim"). However, after the new teachings and doctrines of Isaac Luria (The "Arizal"), in Lurianic Kabbalah, these innumerable Tzimtzumim of the descending chain of Worlds are called the "Second Tzimtzum". Isaac Luria taught the new concept of a "First Tzimtzum", based on earlier allusions in the Zohar. As Lurianic Kabbalah became almost universally accepted in the Jewish development of Kabbalah, nowadays if the term Tzimtzum is used without qualification, it will invariably refer to the first, cosmic, ultimate Constriction taught by Luria (see Tzimtzum). In this radical concept of the "Ari", at the beginning of Creation the Divine "withdrew" (a complete tzimtzum) from a "Chalal" ("Vacated space"), to allow Creation to take place. The interpretation of this forms a central concern of subsequent Kabbalah (see Tzimtzum), and the "withdrawal" of God is interpreted only as a concealment from the perspective of the Creation, and only to apply to His light, not His Essence, as that would imply heretical limitations to the Divine. In Lurianic Kabbalah, the Tzimtzum concealed the Ohr Ein Sof, which resolved the dichotomy between the Infinite Light and the possibility of creating finite Worlds. Without this radical leap of a concealment of the Ohr Ein Sof, even with the progressive, gradual concealments of the Chain of Worlds, the problem would not properly be overcome. Only a second, new light, immeasurably diminished, and of a different quality than the Ohr Ein Sof, could become the creative source of all reality. This new light, a "thin" illumination from the Ohr Ein Sof, called the "Kav" ("Ray"), shone into the "Vacated Space", and was a light that was adapted to the perspective of the subsequent creations on their own terms. It could relate to finite creation (Divine immanence), rather than the infinite Primordial light (the ultimate Divine transcendence). Interpretations of this in Kabbalah and Hasidic philosophy, are careful to avoid literal, spatial, geometric understandings of the Vacated Space and the Kav, as such dimensional understandings relate only to our physical world. Nonetheless, circular diagram representations of this, strictly metaphorical, are used in Kabbalah to represent the process. In the first, a black circle is broken only by one thin, vertical, straight line that descends from the surrounding white into the centre of the black circle from the