John P. Slattery is a senior research associate with the Dialogue on Science, Ethics, and Religion Program of the American Association for the Advancement of Science. Founded in 1995 by the AAAS, the program’s avowed purpose is to facilitate communication between scientific and religious communities. I met the author briefly in 2017 at a conference at Notre Dame devoted to the writings of Fr. Ernan McMullin, and at the time Slattery was keenly interested in an overlooked period of tension between the Vatican and Catholic scientists who were first coming to grips with Darwinian evolution at the end of the nineteenth century. As Slattery’s excellent new book reveals, this period is far more consequential for the checkered history of the Vatican’s relationship with science than the often-overhyped saga of Galileo and the Copernican Revolution.
Slattery’s book focuses on the career and fate of Fr. John P. Zahm (1851–1921), a priest of the Holy Cross at Notre Dame. Zahm’s initially cautious interest in Darwin’s work expanded into an enthusiastic embrace of the idea of biological evolution. This culminated in Zahm’s widely read 1896 book, Evolution and Dogma, in which he argued that the accumulated evidence of the biological evolution of species over the course of the planet’s history in no way presented a challenge to Catholic faith. Quite the contrary, as Zahm wrote:
My sole, ardent desire, has been to show that there is nothing in true science, nothing in Evolution, when properly understood, which is contrary to Scripture or Catholic teaching; that, on the contrary, when viewed in the light of Christian philosophy and theology, there is much in Evolution to admire, much that is ennobling and inspiring, much that illustrates and corroborates the truths of faith.
This was a message that had great appeal to many American Catholics at a time when the U.S. Church was in a period of confident expansion. Notre Dame owed much of its growing reputation as a major Catholic university to Zahm’s tireless efforts. As the university’s vice president he helped expand the school’s library and museum. As a teacher, he traveled around the country giving lectures about the importance of science for Catholics and the compatibility of science and faith.
But not everyone was as enthusiastic about evolution. The success of Evolution and Dogma brought Zahm into direct conflict with the Vatican’s Office of the Index of Prohibited Books, which in 1899 compelled Zahm to withdraw his book from circulation and to cease writing on the topic. These were humiliating demands, but Zahm agreed to them in order to avoid a public censure and keep his book from being placed on the Index. He spent the last two decades of his life traveling around the world and writing more broadly about science, but he never discussed evolution again.