Book excerpt: Jonathan Garb's "Yearnings of the Soul: Psychological Thought in Modern Kabbalah" is an original, path-breaking study of the renderings of the "heart and soul" in the works of major, minor, and obscure but important figures of modern Kabbalah. Garb has unearthed a treasure-trove of neglected figures and texts, bringing into dialogue their views on heart and soul with those found in other religious and secular authorities. There is no other study that comes close to the territory Garb covers or, for that matter, provides the historical and cultural context necessary for understanding the rise of such psychological renderings in the works of the modern Kabbalists. His analysis shows that any attempt to essentialize the multiple and varied understandings of heart and soul in Jewish mysticism is mistaken. Analyzing text and figure in context on a case-by-case basis Garb is able to provide comparison without being reductive. This is an invaluable contribution to the discipline that cements Garb as the leading scholar of modern Kabbalah.