A genuine system of spiritual knowledge should have all the characteristics of a scientific theory. It should provide a logically consistent description of reality and it should entail procedures which can be used to verify important features of this description. The system should be in agreement with existing mechanistic theories in so far as they are valid, but it may be expected to clash with many elements of the modern scientific world view that rest on unsound speculation and extrapolation. Most importantly, the system should contain practical methods of obtaining absolute information about the ultimate meaning and purpose of life. In this book the author tries to make a positive contribution by describing such a system of spiritual knowledge. This means that he introduces a specific system of theory and practice that has been expressed in a particular language and handed down in a particular cultural tradition. Since a practical science must exist in concrete form, it is not possible for me to avoid these details. Nonetheless, his concern is with general principles that are universally applicable. His purpose is to demonstrate the possibility of a scientific system of spiritual knowledge by describing an actual example of such a system. The author does not want to pass judgment on other systems or become embroiled in any kind of sectarian controversy.