"Essays in Radical Empiricism", originally published in 1912. These 12 pieces display the influential philosopher's preoccupation with ultimate reality and his turn toward a metaphysical system. Originally published in journals between 1904 and 1906, these essays argue in favor of a pluralistic universe. James denies that experience can be defined in terms of an absolute force determining the relationships between things and events. "A Pluralistic Universe", originally published in 1909; with the "Essays" considered to be James' most important metaphysical work.