Popes, evolution and the Big Bang

Pope Francis recently said evolution and the Big Bang theory can be compatible with faith in God – a statement that was hardly new, but predictably made news.

The idea that evolution and a divine creator are not mutually exclusive has long been found in the teachings of popes, beginning with Pope Pius XII and his 1950 encyclical, “Humani Generis.” Even so, the mere mention of the word “evolution” by a pope can set off alarm bells. I remember that when Pope John Paul II said in 1996 that evolution was “more than a hypothesis” and had been widely accepted by scientists, some Catholics simply couldn’t believe it.

Perhaps the most complete treatment of evolution came in a 2004 document published by the International Theological Commission, which said evolution makes sense – but only because “God made it so.” That document accepted the basic science behind evolution: that the universe was born 15 billion years ago in a “big bang,” that the earth formed 4.5 billion years ago, that all living organisms on earth descended from a first organism and that man emerged about 40,000 years ago with the development of a larger brain.

A historical footnote is that the man usually credited as the “father” of the Big Bang theory was a Belgian Catholic priest, Monsignor Georges Lemaitre, who was also an astronomer and physics professor. Lemaitre’s ideas were enthusiastically embraced by Pope Pius XII, who had a keen interest in cosmology and who knew Lemaitre through the Pontifical Academy of Sciences. In speeches to the academy, in fact, Pius XII seemed to endorse the Big Bang precisely because he thought it offered scientific evidence of the divine creation of the universe – a “Let there be light” moment. According to contemporaries, after a papal speech along those lines in 1951, Lemaitre spoke with the pope and asked him to stay away from theological endorsements of scientific theories – and Pius took his advice to heart.