In The Gay Science (1882), Nietzsche heralded the problem of nihilism with his famous declaration “God is dead,” which signalled the collapse of a transcendent basis for the underpinning morality of European civilization. He associated this collapse with the rise of the natural sciences whose methods and pervasive outlook he was concerned would progressively shape “an essentially mechanistic [and hence meaningless] world.” The Russian novelist Turgenev had also associated a scientific outlook with nihilism through the scientism of Yevgeny Bazarov, (...) a character in Fathers and Sons. A century or so later, can we correlate relevant scientific results and the nihilistic consequences that worried these and other nineteenth-century authors? The aversion of empirical disciplines to such non-empirical concepts as personhood and agency, and their methodological exclusion of the very idea of value would make this a difficult task. Recent neuroscientific (MRI) investigations into free will might provide a useful starting point for anyone interested in this sociological question, as might the research results of experimental or evolutionary psychologists studying what they take human beings to be. In this paper, I turn instead to a more basic issue of science. I will question the universality of a principle of identity assumed by a scientific understanding of what it means for anything to exist. I will argue that the essential features of human existence present an exception to this principle of identity and thereby fall outside the grasp of scientific inquiry. The basis of this argument will be an explanation of why it is nonetheless rational for us to affirm personhood, agency, moral values, and many more concepts that disappear under the scrutiny of the sciences. (shrink)