Spheres of Reason comprises nine original essays on the philosophy of normativity, written by a combination of internationally renowned and up-and-coming philosophers working at the forefront of the topic. On one broad construal the normative sphere concerns norms, requirements, oughts, reasons, reasoning, rationality, justification, value. These notions play a central role in both everyday thought and philosophical enquiry; but there remains considerable disagreement about how to understand normativity -- its nature, metaphysical and epistemological bases -- and how different aspects of...