I recently finished the latest book of psychoanalyst, research psychiatrist, and pioneer in the field of adult development, Dr. George E. Vaillant. The book, Spiritual Evolution: A Scientific Defense of Faith, is in part a secular form of apologetics for faith, spirituality, and religion as well as an examination of the emotional qualities that define our lives and make us human. As a whole, it is a rare gem bridging the contemporary divide between the worlds of science and belief.

I was relieved to find in this book a clear definition of spirituality which, as a student of religion, has often proved an elusive and frustrating term. Vaillant defines spirituality as “the amalgam of the positive emotions that bind us to other human beings – and to our experience of “God” as we may understand Her/Him.” Agree or no, props to him for attempting to qualify a vague and overused expression.

The positive emotions Vaillant mentions could be many, but he chooses to focus on love, hope, joy, forgiveness, compassion, faith, awe, and gratitude; note that these emotions are predominantly communal opposed to individual. After discussing the development of positive human emotion and the distinguishing characteristics of our limbic system (the primary neurological agent of human spirituality) Vaillant devotes a chapter to each of the eight selected emotions, mapping their purpose, expression, and value with clear and engaging prose. So even if your eyes glaze over at the thought of neuroscience and human evolution the bulk of the book should prove deeply satisfying.

Vaillant’s primary argument is: not only do faith and spirituality play a role in human life, but they are essential qualities we have evolved to survive as a species. After reading Vaillant’s observations, I am thankful to say there is now a voice to answer the caustic charges of brilliant if obsessive (read: dogmatic) thinkers such as Sam Harris and Richard Dawkins, who proclaim faith and religion the greatest enemies of humanity in the twenty-first century.

Vaillant juggles mental development, neurological science, psychology, religion, and spirituality with precision, clarity, and manages not to belabor the reader with jargon and dry analysis. He weighs the impacts of cultural vs. genetic evolution, and highlights the significant cultural evolution of the “Axial Age” whose thinkers, from Buddha to Muhammad, are the progenitors of every major world religion alive today. With all the turmoil and hatred surrounding modern religions we may forget that the faith upon which those institutions developed is rooted in compassion, forgiveness, and love. And I am confident, their founders would weep to see the misogyny, bigotry, and ignorance consuming the institutional belief systems of the present.

But back to Vaillant. He is clearly a man of science but also a passionate writer whose book comes across as a life’s work and a heart felt endeavor to secure a place for the spiritual even in the absence of belief or religiosity. The positive emotions discussed benefit humanity at large (i.e. as a species), communally, and on the intrapersonal level. He is quick to mention, the emotions that imbue our lives with substance and meaning do not depend upon any doctrine or metaphysical analysis of reality; they are shared experiences that provide the grounds for empathic connection, or (to wax most Buddhist) examples of our intrinsic interconnection. So if you are a seeker, a skeptic, both, neither, or if you simply enjoy reading the works of those who endeavor to bring substance to our lives; then this is a book for you.