Sleep is one of the greatest riddles of existence. It is an absolute necessity for the refreshment of each one of us, yet natural science can give virtually no explanation of how this is done. And the reason for this is clear; it is not only a natural, but also primarily a spiritual process. Understanding therefore depends on the research of the spiritual scientist, and preeminently on that of Rudolf Steiner. This book is the first integrated account of the many aspects of sleep that Steiner described, and the first to outline the bodily processes involved in anthroposophic terms.

This study opens up awareness of our little-known relationships with the cosmos and its beings, in which we all spend a significant portion of our life.