Very interesting. Let’s turn to your first choice, A Secular Age by Charles Taylor, which traces the processes of secularisation in the modern age.

Charles Taylor, a Canadian Catholic philosopher, is among the most notable thinkers on these themes in North America these days. This is a massive, almost 800-page book that really attracted attention and debate. He argues that most can’t really make sense of the modern world or life today without some version or other of religion. He defines religion very broadly. He is not pointing to Christianity or Judaism or any other faith to carry all the meanings, but instead speaks in the broadest sense of how the human relates to the transcendent order, to that which is ‘beyond us’ etc. This is not what you normally expect from a philosopher. Taylor is running against the grain of much modern philosophy, since it has dispensed with such matters. He gave me a lot of reason to rethink some themes in the book I was writing about Dietrich Bonhoeffer’s Letters and Papers from Prison.

What kind of things did he make you rethink?

The notion that the 18th-century Enlightenment and its heritage had pretty well finished things off. In other words, if you reach back to the Middle Ages of Catholicism and the Anglo and Continental reformations of the 16th century, religion dominates. For instance, when the Protestant reformations were over the church was still established in England and most of Europe for centuries. The Protestants were doing the same thing that the Catholics had done before them. They couldn’t conceive of a society in which God didn’t rule through the rulers. But then came the Enlightenment – the great burst of scepticism and criticism in a time when philosophers and scientists took over and offered a new kind of accounting of the world. Most stressed the empirical, which meant that you had nothing to say unless it was based on something you could see or touch or smell. Such an outlook was predominant from the 18th century onwards, in the 19th century taking more radical forms and in the 20th century even more so. Moderns take that for granted. Bonhoeffer looked out on that world and dealt boldly with it.

I am Christian and yet I know that if I want to communicate many kinds of things I do them without reference to a transcendent order. Taylor, without naming him, challenges Bonhoeffer’s description of this ‘world come of age’. He finds that to be a very unsettling settlement because it is hard to provide a basis for our decisions. What is good and what is true and what is beautiful when all is only a matter of our own emotions? Somehow or other we have to pay attention to deeper stirrings. I think Taylor’s thoughts have presented a challenge to this ‘secular’ side of Bonhoeffer.

So this book has really stirred up your community?

Oh, yes. Many universities are having conferences on it and elaborating on its theme. Sometimes he repeats himself but the second time around you learn something you didn’t the first time. You are never going to be quite as ready as before to lean back into a simple scientific agnosticism. Taylor is not preaching a sermon or setting out to convert you but he does want to raise deep questions as to whether we have mastered the world the way we thought we did two centuries ago.

Your next book looks at one of Christianity’s great thinkers, St Augustine. R A Markus’s book, Saeculum: History and Society in the Theology of St Augustine, explores how his ideas relate to the world he was living in.

Almost everyone who confronts this slim 47-year-old book testifies that it brought a fresh understanding of the monumental ancient Christian thinker, St Augustine. Why, you may ask, should he show up when we are trying to make sense of the world around us, and, in the present case, of Bonhoeffer’s letters? Well, what Augustine argued was quite radical. We think of him as one of the four or five greatest Western Christian thinkers, one who is not shelved in the ancient world but who still frames much thought of people who have never heard of him. This book’s title deals with the saeculum, the Latin word for ‘this age’.

Augustine took up his theme with an effort to secularise Roman history. His world, 400 years or so after Christ, was a world where many still evoked the old gods of Rome by citizens who saw Rome as sacred. But Augustine said, no, the state may be a wonderful human invention, which needs criticism. So he dealt in undercutting ways with the old political order and ‘civil religious’ order.