After studying at several European universities, Keyserling began a world tour in 1911 that provided the material for his best-known work, Das Reisetagebuch eines Philosophen (1919; The Travel Diary of a Philosopher). Keyserling's approach to philosophy was essentially nonacademic, and his ideas, which centred on the theme of spiritual regeneration, were often platitudinous or obscure. His other works include: Unsterblichkeit (1907; Immortality), Schöpferische Erkenntnis (1922; Creative Understanding), Wiedergeburt (1927; The Recovery of Truth), America Set Free (1929), and Südamerikanische Meditationen (1932; South American Meditations).