To describe Robert Cummings Neville as prolific would be a thundering understatement. Professor of Philosophy, Religion, and Theology and Dean Emeritus of the School of Theology at Boston University, Neville is one of the founders of contemporary comparative theology in North America, a leading light of Boston Confucianism, and possibly the most relentlessly constructive disciple of Paul Tillich currently active. He has authored or edited something in the neighborhood of forty books, and his career is punctuated by impossibly bold titles such as Reconstruction of Thinking (SUNY Press, 1981) and Existence (SUNY Press, 2014). Defining Religion is a no less ambitiously titled collection of essays and personal communications that Neville authored while he was working on his three-volume Philosophical Theology (SUNY Press, 2013–2015). It functions as a kind of précis of that work, intended especially for the benefit of those “many people” who might find the systematic architecture of the larger study “hard to take” (xii)—which, it must be admitted, well describes the present reviewer.

Defining Religion is neatly divided into five groups of four chapters each, entitled “Heuristics,” “Pragmatics,” “Religious Studies,” “Philosophical Theology,” and “Players.” Suspicious readers may wonder whether this arrangement is too elegant to be believed, with good reason. I suggest approaching the volume instead as two different works, each with its own integrity. In “Heuristics,” “Pragmatics,” and perhaps the first chapter or two of “Religious Studies,” the essays have been effectively revised and organized to offer a coherent theory of religion, religious experience, and the rectification of disciplinary frameworks for their continued study. The remainder is a fairly standard collection of occasional writings, varying considerably in quality and relevance. This second “book” is not devoid of value. Far from it: chapter 13 may be the best essay in the volume. A long letter to the process thinker David Ray Griffin, this chapter skilfully orients readers new to Neville's basic theological commitments, his warm humanity, and the vital importance of respectful disagreement in the scholarly project.

Nevertheless, it is the first “book” of Defining Religion that most rewards a careful read. According to Neville, religion is best understood as “human engagement of ultimacy expressed in cognitive articulations, existential responses to ultimacy that give ultimate definition to the individual, and patterns of life and ritual in the face of ultimacy” (9, italics original). The key terms here are “ultimacy” and “engagement.” With regard to the former, Neville offers a creative redeployment of Tillich's category of “ultimate concern,” translated into the idiom of American pragmatism and deeply informed by the history of religions. With regard to the latter, Neville reveals his debt to the semiotic theory of Charles S. Peirce (1839–1914). A good example is his discussion of religious experience. Neville insists that what makes an experience “religious” is not a particular quality of the experience, much less its sociological or neurological basis. Religious experiences are distinguished not by their distinctive phenomenology, but by their distinctive object: “a religious experience is the experience of something religious” (84) or, stated more precisely, “an interpretive engagement of ultimacy” (95). One task of the philosophical theologian, then, is to trace these patterns of interpretation and to advance hypotheses about the realities they engage. This is, in the framework proposed by Peirce and other pragmatists, a semiotic project.

Few readers will agree with all or even most of Neville's conclusions in Defining Religion. For the traditionalists among us, his construction of God in terms of determinacy and contingency upsets more than a few sacred apple carts. “Metaphysics,” he concedes, “… is often not satisfying to an ingroup approach to religion because it insists on being indifferently related to all that might fall under it” (118). It is, at the same time, deeply refreshing to encounter a thinker so sympathetic to scientific and postmodern heuristics who is also so thoroughly committed to engaging God and the natural world as realities that can and should be known through the exercise of human reason. It offers scholarly peers and advanced graduate students an excellent introduction to key themes of Neville's thought … and to the idea of philosophy of religion as a still viable project in the contemporary academy.