Rudolf Christoph Eucken (1846–1926) was a German philosopher whose work emphasized the spiritual dimension of human life and the active pursuit of truth through ethical action. A professor at the University of Jena for more than forty years, he developed an influential form of idealism that sought to reconcile philosophy, religion, and modern science. His major works include The Problem of Human Life, Life's Basis and Life's Ideal, and The Meaning and Value of Life. Awarded the Nobel Prize in Literature in 1908 for his earnest search for truth and his idealistic philosophy, Eucken remains one of the few philosophers to have received the honor.

- Der Sinn und Wert des Lebens 1908 non-fiction philosophy de