Rudolf Steiner 
The Wisdom of Theosophy 

This book will give a description of some of the regions of the supersensible world. The reader who is willing to admit the existence of the sensible world only will regard this delineation as a mere unreal production of the imagination. He, however, who looks for paths that lead beyond this world of the senses will soon learn to understand that human life only gains in worth and significance through sight into another world. Such a man will not, as many fear, be estranged from the "real" world through this new power of vision. For only through it does he learn to stand fast and firm in this life. He learns to know the causes of life, while without it he gropes like a blind man through their effects. Only through the understanding of the supersensible does the sensible "real" acquire meaning. One therefore becomes more, and not less, fit for life through this understanding. Only he who understands life can become a truly practical man.