 James made some of his most important philosophical contributions in the last decade of his life. In a burst of writing in 1904–5 (collected in  Essays in Radical Empiricism (1912)) he set out the metaphysical view most commonly known as “neutral monism,” according to which there is one fundamental “stuff” that is neither material nor mental.  In “A Pluralistic Universe” he defends the mystical and anti-pragmatic view that concepts distort rather than reveal reality, and in his influential Pragmatism (1907), he presents systematically a set of views about truth, knowledge, reality, religion, and philosophy that permeate his writings from the late 1870s onwards.