This book is a study of the metaphysical scheme known as the Kabbalistic Tree of Life, based upon ancient, medieval and modern views of its principles. The structure and dynamic of Existence are described in great detail, for instance in the workings of economics, the course of a love affair and the progression of evolution. Such examples reveal how cosmic laws operate throughout the four interconnected Worlds of Jacob's Ladder. Within this scheme, the purpose of humanity is explained in terms of different levels of physical, psychological and spiritual development. We are part of the interaction of matter, form and creation in a vast process that originates in the Divine Realm.