Indian Brahminic philosophy. For Schweitzer, mankind had to accept that objective reality is ethically neutral. It could then affirm a new Enlightenment through spiritual rationalism, by giving priority to volition or ethical will as the primary meaning of life. Mankind had to choose to create the moral structures of civilization: the world-view must derive from the life-view, not vice versa. Respect for life, overcoming coarser impulses and hollow doctrines, leads the individual to live in the service of other people and of every living creature. In contemplation of the will-to-life, respect for the life of others becomes the highest principle and the defining purpose of humanity. Such was the theory which Schweitzer sought to put into practice in his own life. According to some authors, Schweitzer's thought, and specifically his development of reverence for life, was influenced by Indian religious thought and in particular the Jain principle of ahimsa, or non-violence. Albert Schweitzer noted the contribution of Indian influence in his book Indian Thought and Its Development: Further on ahimsa and the reverence for life in the same book, he elaborates on the ancient Indian didactic work of the Tirukkural, which he observed that, like the Buddha and the Bhagavad Gita, "stands for the commandment not to kill and not to damage". Translating several couplets from the work, he remarked that the Kural insists on the idea that "good must be done for its own sake" and said, "There hardly exists in the literature of the world a collection of maxims in which we find so much lofty wisdom." Later life After the birth of their daughter (Rhena Schweitzer Miller), Albert's wife, Helene Schweitzer was no longer able to live in Lambaréné due to her health. In 1923, the family moved to Königsfeld im Schwarzwald, Baden-Württemberg, where he was building a house for the family. This house is now maintained as a Schweitzer museum. From 1939 to 1948, he stayed in Lambaréné, unable to go back to Europe because of the war. Three years after the end of World War II, in 1948, he returned for the first time to Europe and kept travelling back and forth (and once to the US) as long as he was able. During his return visits to his home village of Gunsbach, Schweitzer continued to make use of the family house, which after his death became an archive and museum to his life and