G. E. R. Lloyd's economically persuasive study addresses the question of the universalism or relativism of rationality. Drawing careful comparisons, primarily between ancient Greek and Chinese thought, but also more widely, Lloyd introduces a range of disciplinary perspectives and specific points of focus. In doing so, he challenges his reader to think critically about their own assumptions and concepts. In particular, he asks us to consider the degree to which our own broad concepts, especially oppositions such as between rationality and irrationality, are themselves informed by their derivation from ancient Greek thought. His first chapter (‘Aims and Methods’) introduces his central commitments. Rationality and irrationality are not universal across societies in such a way that they can be judged by a single set of criteria. But nor are they just cultural constructs, so that the possibility of mutual intelligibility collapses. The truth lies somewhere in between, in the recognition of the heterogeneity to be identified in what is shared across cultures. Lloyd argues that ancient China is a particularly useful foil for a consideration of these questions, since it provides a perspective from beyond the reach of the Graeco-Roman legacy. His subtle middle road is further supported by his second chapter (‘Rationality Reviewed’), which summarizes some influential accounts of rationality and considers the ‘state of play’ across a variety of disciplines, including palaeontology, child development, and psychology, all of which present evidence of continuities between societies. The next four chapters approach the question of the diversity and commonality of reason from a range of perspectives, including cosmology, metaphysics, language, epistemology, and religion. In the case of cosmology, for example, Lloyd argues that we can identify a difference between the Greeks’ tendency to focus on the thing that is ‘Nature’, and the Chinese interest in natural phenomena and processes, absent a concept of ‘Nature’ itself. He is careful to note the difficulty of generalizing across all Greek or all Chinese thinkers. We can, however, identify a significantly similar belief in the two societies: that understanding the cosmos matters for the sake of the life you live as a result of that knowledge. In the case of the binary ‘Seeming and Being’ (as discussed in Chapter 4), Lloyd argues that the Chinese shared with the Greeks an awareness that appearances can be deceptive. However, their conception of the fundamental binary yin and yang is one of interdependence rather than sharp differentiation, such as we sometimes see in Greek thought between Being and Becoming. Throughout the volume, Lloyd argues for the need to recognize both the similarities and the differences identified as a result of careful comparative study. He ends with a recommendation for his readers to reconsider the universal applicability of certain key Western concepts, without resorting to a claim that it is impossible to recognize or communicate similarities. We must, he suggests, work from a position that demonstrates ‘due recognition both of the commonalities in human cognitive capacities, and of the differences in their deployment’ (96).