Jerusalem, the last and most fully developed version of Blake's personal myth, is recognized as an important part of our cultural heritage, apparently full of deep meaning. But exactly what that meaning is has been little understood. At first sight Blake's poem lacks narrative continuity, presents no clear argument and shows little structural cohesion, while his illustrations, beautiful though they are, are often difficult to relate to the text. Yet underlying its baffling surface there is a coherent and relatively simple pattern, and this reveals in a unique way the psychological and spiritual processes that shape our lives and give them direction.