Yonghua Ge reviews Lydia Schumacher’s Theological Philosophy: Rethinking the Rationality of Christian Faith

Apologetics, the discipline that defends the reasonableness of faith against its critics, has been an important and fascinating part of Christian thought. Indeed, some of the earliest Christian thinkers—Justin Martyr and Tertullian, for instance—were apologists. Throughout the centuries, theologians and philosophers have provided various arguments for the rationality of faith. But after Kant’s devastating critiques of traditional arguments for God’s existence and in light of the post-modern suspicion of truth claims, apologetics as discipline seems no longer possible or desirable. It is thus refreshing to see a book entitled Theological Philosophy: Rethinking the Rationality of Christian Faith, in which the author, Lydia Schumacher, claims to take a novel approach to apologetics. As part of the Transcending Boundaries in Philosophy and Theology series, which seeks to explore “new opportunities in the dialogue between philosophy and theology that go beyond … traditional ‘faith and reason’ debates,” Schumacher’s book contends that Christian faith is by nature rational as it provides “a rational for rationality.” The argument of this book, however, builds on the thesis of her previous book Rationality as Virtue: Towards a Theological Philosophy (Ashgate 2015), in which she argues that rationality is ultimately about ethics—knowledge is used to maximize the flourishing of humanity. Reason thus defined is not inimical to but presupposes faith. It is therefore possible to develop a “pro-theology philosophy.” The present book fleshes out such a philosophy by demonstrating that Christian faith promotes human commitment to the highest good and hence is intrinsically rational.

The book begins by laying out the foundation for a theological philosophy that aims to foster the maximization of human flourishing. Drawing from Aquinas, the author suggests that, to realize human potential, we need four cardinal virtues, namely prudence, justice, fortitude, and temperance. Since self-realization presupposes an accurate self-assessment, prudence is needed to avoid hubris and false humility that prevent us from actualizing our potential. The second virtue is justice, which is essentially prudence in the context of interpersonal relations. Justice requires that persons and parties receive assistance “equal to their capabilities and needs.” The last two virtues, fortitude and temperance, regulate our passions so that we can operate with prudence and justice.

Having outlined the conditions for pursuing the highest good, Schumacher proceeds to demonstrate how belief in the Christian God, who is transcendent, triune, and incarnate, provides a rationale for that pursuit. As I will expound later, this is both the most interesting and most controversial part of the book. In any case, Schumacher contends that because human beings tend to ascribe absolute significance to finite goods, it is necessary to affirm the reality of a good that is beyond all limited goods and utterly irreducible to them. This good is secured by the existence of a transcendent God, who is simple, eternal, and perfect. However, to have clear knowledge of the transcendent God, we must rely on his self-communication and this self-communication is possible only through his Triune nature, which was most explicitly revealed to us by the incarnate Son, who empowers us to become fully human and orient our lives toward the highest good. Together, the doctrines of transcendence, the Trinity, and the incarnation provide the fundamental basis for pursuing the highest good or rationality, which is nothing but “participation in the life of the Triune God.”

The next section discusses how the other key doctrines – creation, sin, redemption, and church – elucidate and facilitate our participation in God. While the doctrine of creation establishes the nature of participation in God, the doctrine of sin explains the reason why participation is impeded. Subsequently, the doctrine of redemption describes the way in which God reopens the possibility of participation, while the doctrine of the church discusses the restored human life at individual and communal levels. These four doctrines thus constitute what the author calls “Christian Creedal Reasoning” for theological philosophy.

While the above discussions operate on the doctrinal level, the book now returns to the ethical aspect. Schumacher tells how within the framework of Christian doctrine the theological virtues of faith, hope, and love enable us to pursue the highest good. Because sin at its core is a deviation from God, faith re-orients our lives toward God and is thus the starting point of our participation in God. Then by living in hope, humans are actually moved gradually toward God as the highest object of desire. Finally, love is “the sign that faith has been made effective by hope” and hence the evidence of a transformed life pursuing the highest good. The book then elaborates on the nature of love in terms of the four moral virtues of prudence, justice, fortitude, and temperance, as outlined earlier. Here, the book goes back to its starting point, demonstrating how Christian love, as a consequence of Christian faith, maximizes the virtues that are foundational for realizing the highest human good. In fact, prudence, justice, fortitude and temperance become respectively the personal, interpersonal, instructive, and persuasive powers of love. Ultimately, love is the optimal site for the human pursuit of the highest good, in which rationality consists. In this sense, as the author points out, “the ultimate ‘proof’ for the rationality of faith consists in the life of Christian love.”

Schumacher’s book is an inspiring new addition to contemporary literature in apologetics and the philosophy of religion. Unlike many traditional arguments for the rationality of faith that focus on epistemology, Schumacher’s ethical approach is certainly refreshing and stimulating. She rightly reminds us that the reasonableness of Christian faith does not rest on arid intellectual debates but on Christian life. After all, faith is not simply a cerebral issue but a commitment to a certain way of living. In this respect, the book stands in continuity with Stanley Hauerwas’ line of argument that the proof of faith ultimately derives from the life of the Church. Yet, through a sophisticated redefinition of rationality, Schumacher is able to rest this contention on a more solid philosophical foundation, which I believe is the main contribution of this book. As a volume in the Transcending Boundaries in Philosophy and Theology series, Theological Philosophy is largely successful in achieving the goal of breaking down modern barriers between the two subjects, although a clear distinction exists between them in Aquinas’s thought, from which Schumacher draws heavily. She admits from the outset, however, that she would adapt – rather than simply follow – Thomas.

Reading through this book, one cannot help but wonder who the target audience would be and how much the validity of its argument depends on the background of its audience. For Christians who share the presuppositions of the author, the book is indeed convincing, as it provides helpful intellectual tools for affirming the rationality of their faith. Indeed, many apologetic works are more for believers than for non-believers. But apologetics must also serve non-believers. My impression is that the book is less persuasive for them. While it claims to be a philosophical work, some parts of the book – especially chapter 4, “Creation and Fall,” and chapter 5, “Redemption and Church” – read like a systematic theology handbook. In seeking to overcome the barrier between philosophy and theology, the book may have gone too far by blurring the distinction between the two disciplines, and since the author does not provide a clear definition of either term, it is sometimes unclear what she means by “theology” or “philosophy.” Yet if no distinction exists between the two terms, why call the book “Theological Philosophy”? Failing to clarify the relation between philosophy and theology also leads to another difficulty. In chapter 3, “Necessary Conditions for Theological Philosophy,” Schumacher argues that to promote commitment to the highest good it is essential that there is a transcendent, Triune and incarnate God who communicates himself and can be comprehended by humanity. Such an argument seems to suggest that the theological doctrines of transcendence, the Trinity and the incarnation are not truly revealed mysteries beyond reason but more or less logical necessities. This reminds us of Anselm’s effort to prove the necessity of the incarnation, which was explicitly rejected by Thomas. For in such cases, theology is reduced to philosophy and mystery to knowledge. For these reasons, Schumacher may still need to maintain a distinction between philosophy and theology.

Overall, this is an impressive, creative, and highly original piece of theological work. It makes an important contribution to apologetics and the on-going debates about faith and reason. I would recommend it to anyone who is interested in apologetics and the philosophy of religion.

Yonghua Ge (PhD. Cambridge University) is a Post-Doctoral Fellow at Regent College, UBC and Distinguished Research Fellow at the School of Philosophy, Beijing Normal University. He has published articles in Philosophy East and West, Tyndale Bulletin, The Heythrop Journal, Sino-Christian Studies, Logos & Pneuma (HK), Crux, Chinese Social Studies Today, and Regent Review of Christian Thoughts.