Reviewed by: The Concealed Influence of Custom: Hume’s “Treatise” from the Inside Out by Jay L. Garfield John Christian Laursen Jay L. Garfield. The Concealed Influence of Custom: Hume’s “Treatise” from the Inside Out. Oxford: Oxford University Press, 2019. Pp. 302. Hardback. ISBN: 978-0-19-093340-1, $82. This book has at least two original and great merits. One is that it is one of the first in the Hume literature to be truly global. The other is that it gives custom and habit the place they deserve in Hume’s philosophy. Concerning the first of these, I think it would be widely admitted that most of the study of Western philosophy is done in blissful ignorance of non-Western philosophy. We follow what our thinkers are doing, and pay little or no attention to the rest of the world. In contrast, this book peppers the footnotes, and even some of the text, with comparisons to Buddhist schools and figures such as Madhyamaka, Candrakirti, Nagarjuna, and the like. We are not used to the idea that Western philosophers may have drawn some of their ideas from non-Western philosophy, although we have long known that Pyrrho traveled to India and may have taken ideas from the gymnosophists, and that later philosophers like Bayle and Leibniz were very interested in Chinese ideas. In Hume’s case, it is possible that there was some influence through Pyrrho and his followers, or that these were simply parallel developments. The latter are still of philosophical interest because they show how similar philosophies can develop from different roots. Of course, one of the reasons that most of us cannot compare a figure like Hume to Indian or Chinese philosophy is that we do not know the languages and have not been trained in those areas. In this case, Jay Garfield is the author of many works on Indian philosophy, including Engaging Buddhism: Why it Matters to Philosophy (2015), so he has authority in the matter. A work like this, drawing attention to many similarities and parallels in philosophy, could be followed up by some methodological work on how to compare philosophies from such different intellectual traditions. What do the parallels mean? Are there any deeper or wider conclusions that we can make about parallels that appear in very different philosophical traditions? Is convergence of ideas a confidence builder in their solidity and truth, or rather a reminder of common human tendencies to fallacy? If philosophy is ever going to join the ranks of truly global human enterprises, it will have to ask and answer these questions about far-flung philosophical traditions. The main argument of this book is that Hume is best understood as a Pyrrhonian philosopher who maintains that the foundations of our knowledge, ethics, and political practices may be found only in custom and habit. Book 2 of Hume’s Treatise is the key, providing a social account of the passions and our constructions of ourselves. “Custom is essential to the story,” the author writes (82). Nature makes [End Page 179] us develop customs together that start from passions and sympathy, and are drawn together by the imagination. On the basis of these social constructions of most elements of our lives, by the end of the book, Garfield is talking about Hume’s place in the “communitarian tradition” (279–80). If Book 2 is read before Book 1, one will realize that what Hume says about reason and ontology in Book 1 is rooted in his theory of the passions in Book 2, and thus always social. What Hume is doing is more like philosophical psychology (or the psychology of philosophy?) than epistemology, metaphysics, or moral philosophy, according to Garfield. Hume is asking why we believe what we believe in epistemology, metaphysics, and moral philosophy, not proving that any of these beliefs are true. Taking the title of Hume’s Treatise seriously, it is a book about human nature, not about Hume’s understanding of those philosophical subfields. Hume’s work is more descriptive than prescriptive. We can learn from it how we live, not how we should live, which is a matter for the development of customs over time...