Brendan Purcell’s From Big Bang to Big Mystery is a unique contribution to the understanding of human origins. No one else has explained so clearly why creation and evolution are both needed if we are to understand ourselves. The external record of evolution charted by science is incontrovertible. But so is the long history of the symbols by which human beings interpret the source of their existence. Neither perspective can be jettisoned. We do not have to choose between an evolutionist and a creationist account. Human origins must be understood on both paths simultaneously. This is what Purcell accomplishes in a great contemporary summa of science and faith. This book shows how the external record meticulously charted by science must be integrated with the equally vast internal record of the human search for meaning.

A concept of human unfolding that fails to account for the intelligence that grasps it must remain unsatisfactory. Equally, a version of the material evidence that requires a God of the gaps is an insult to the same intelligence. The great challenge has been to find a notion adequate to the multiple dimensions of reality. Purcell finds this in Bernard Lonergan’s idea of emergent probability. The layers of being, from the inorganic, to the organic, to the sentient, up to the rational, have been a feature since Aristotle listed them. But so far there has been no model of their relationship, apart from dualistic or reductionist alternatives.

How can biology be related to chemistry without being reduced to it? How can thought be anything more than neurophysiology? Purcell has deepened and enlarged the notion of emergent probability to fashion it as the major theoretical linchpin of the understanding of origins. Emergent probability explains how what is random at one level becomes integrated at a higher level to produce a different kind of reality. What at the level of particle physics may appear as random movements is grasped at the level of chemistry as a distinct regularity. This, as Purcell explains, is why the infamous problem of the gaps in the fossil record that so concerned Darwin and inflamed his critics is a non-problem. The emergence of species can occur only when the prior emergence has provided the material basis on which a higher form can emerge. “Punctuated equilibrium” is not a fallback but what is to be expected in a world built on the leaps constituted by emergent probability.

It is a notion that does not necessarily resolve the mystery of the emergence of life, but it does reveal the structure of that mystery without diminishing it. At the very least, emergent probability demonstrates the possibility of the intellectual shift so badly needed in the study of human origins. Purcell does a superb job tracing the growing pressures within the field, which center on the lack of an adequate definition of what it means to be human. Paleoanthropologists are most acutely aware of the problem since they are tasked with distinguishing human beings as such. It is the central philosophical question that Purcell has taken as the burden of his work.

He has made a remarkable contribution by demonstrating that the question cannot be answered externally. No one can say what a human being is by confining the study to what is outside. No amount of material evidence will yield a satisfactory definition, for we are compelled to enter into the symbolic self-presentation that human beings have always initiated. With all other species, the external remains represent them. Human beings are different in representing themselves. It is the emergence of inwardness that marks humanity, an inwardness that goes far beyond the basics of consciousness. It is human beings alone that are capable of the kind of detachment that enables them to search for origins they have already gone beyond. With humanity reality has gained inwardness and is contained within it.

Purcell is virtually alone in confronting the full implication of this realization—that human beings who can reflect on their origins can nowhere be contained in the record they leave behind. Only the full historical reach of their self-reflection can approach an adequate account of what remains inexhaustible. This is the great insight that Purcell gained from Eric Voegelin, who also employed the term “philosophical anthropology” before ultimately conceding that it is only partially approached within the whole historical unfolding. The nature of man is history.

From Big Bang to Big Mystery proclaims the obsolescence of the opposition between the sciences and humanities. Not only do they address the same human reality, but they are mutually indispensable. What kind of science would it be if it left out the most crucial aspect of what counts as human? What kind of humanistic understanding can ignore the long material evolution that provides the basis of human life? Our modern world has long aspired to integrate the disjointed perspectives of faith and reason, of experience and fact. In Purcell’s study we have a model developed, not in abstraction, but within the scientific and spiritual imperative for self-understanding.

Confident, like St. Thomas, in the unity of truth, Purcell has been able to find a way toward that more capacious vision. Animated by the scientist’s love of empirical cases, the intricate marvels of the universe, he has never lost sight of the deeper spiritual affinity that carries him forward. In the end, it is Purcell’s own generosity of spirit that deeply stamps the work. Love is not too strong a word. There are no opponents or competitors in the enterprise in which, with Antoine Saint-Exupéry, “it is only with the heart that one sees rightly.” It is in reaching out toward all others that Purcell leads us toward the Love that makes it all possible.

In the end the only adequate perspective is that of God, for whom each person is the center of the whole universe. Science, if it is to be true to itself, must ultimately reach that admission, for that is the condition of its own possibility too. Love is stronger than death, including the love that drives the investigation of reality, for the scientist has already set his or her own survival aside. In the end the only adequate account of human origins is one that is able to include its own magnificent witness to self-transcendence. Otherwise we are assailed by the “horrid doubt” that afflicted poor Darwin in those moments when he forgot that he already surpassed a monkey in prioritizing truth over his own convictions. Brendan Purcell’s book is itself a big bang in its affirmation of the faith that sustains the science of origins in the face of the doubts that assail it. It is faith in the end that carries us toward a deeper investigation of the beginning.

Listen to an interview with Brendan Purcell.

David Walsh is a professor of politics at The Catholic University of America, Washington, D.C.