Rudolf Steiner's superb thesis provides deep insight into spiritual science, and the history of mankind as viewed through the philosophy of the anthroposophy movement he founded. An Outline of Esoteric Science attempts to reconcile mankind's spiritual being with the scientific exactitude which had emerged among scholars in the 19th century. Steiner lays out the spiritual realms which are invisible to us, attempting to use a defined precision similar to that which had emerged in science. In the final section, this book refers to the spiritual development and contemplation necessary for individuals to see the spiritual realms and planes which comprise existence and the universe. The means by which individuals may train themselves introspectively to see are detailed by Steiner, whose theosophical philosophy was, by the time of this book's publication in 1909, well-developed.

Helena Blavatsky's translations of three fragments of ancient Buddhist wisdom, sourced from texts such as The Book of Golden Precepts, are contained in this thought-provoking volume. A valiantly sought collection of sage advice and spiritual instruction, The Voice of the Silence offers readers advice on inner growth. Principally the text echoes the principles of Buddhism, advising readers to put aside personal desires and focus upon fostering the inner wealth of the soul to achieve a life of contentment. Blavatsky's book was published as part of her personal investigations into ancient wisdom pertaining to the human soul and reality. Her hunt turned up the formerly obscure fragments which she painstakingly translated. Although existing scholars generally poured cold water upon her efforts, which they considered a haphazard grouping of ancient precepts and mysticism, the reception was warmer among readers discovering the theosophist principles of spiritualism for the first time.

The self-conscious human soul participates in two worlds: the external world and a still deeper interior world. As it mediates between these two worlds, an evershifting stream of dynamic polarities continually moves through the soul in love-hate, joy-sorrow, pleasure-displeasure, desire-satisfaction, and laughing-weeping. The author examines these and other psychological processes.