This chapter focuses on the experimentalist philosophers of the period whose work would also bear much comparison with Friedrich Nietzsche and Henri Bergson, William James and Ludwig Wittgenstein. Wittgenstein’s analytic philosophy thus emerges in quite the same terms as James’s pragmatic philosophy. In making sense of James’s many critiques of idealism, and the importance of those critiques for the genesis of his pragmatism, it is crucial to begin with a distinction between James’s pragmatism and his radical empiricism. The chapter considers how differently James’s celebrations of indeterminacy play out on the register of practice in contrast to how they manifest as present in experience. G. E. Moore and Bertrand Russell criticized idealism according to a path that opened up the development of precisely that which James had found most objectionable in idealism, its commitment to philosophical necessitarianism in the form of contradiction thinking.