We would see each other when our schedules permitted, so that we had the feeling of being short-changed, of not having the time to really get to know the other’s personality or their faults. And while I had plenty of faults, he had one big one: he believed in God. Philippe, this man who was integrity personified, intelligent, cultured and witty . . . believed in God! It just seems so unlikely that anybody could give any credibility to such a load of rubbish. He could have confided in me a belief that our fate as humans was pre-determined by a dish of celestial noodles, and I would have found it less ridiculous.

One day, when I was taking my daughters to the Natural History Museum, I remember seeing a couple of Saudi tourists: a woman in a niqab accompanied by her husband. At the time, there was a lot of talk of creationism in the United States and you’d often come across nonsense like the fact that dinosaurs disappeared because they were too heavy to climb onto Noah’s Ark.

I’m an Arabic translator, and therefore supposed to know everything about Arabs, the religion included — you should know that in Arabic, there’s hardly a sentence without a reference to Allah — so I couldn’t resist approaching this rather unusual couple to enquire as to the precise Islamic view of dinosaurs. You got the feeling the guy didn’t know quite what to think of these immense creatures. He introduced himself as a professor of theology at the Sharia College in Riyadh. After some time reflecting, all the while stroking his beard, he told me with a learned air that there were some verses in the Quran that spoke of the creation of the universe in six days, but that the length of the days was not clearly specified, given that the sun, the stars . . . all of those things . . . weren’t really set up, and therefore there was nothing stopping you from envisaging days that were several million years long. The resulting ambiguity accordingly left open the possibility of a very old Earth populated by these huge animals. But to go from there to saying that man was descended from apes or from a bacteria, as suggested by the frescoes at the entrance to the museum: well, that was the stuff of infidels! He finished by inviting me to undertake my Hijrah — that is, to leave France to go and live a wholesome Islamic life in a holy land where such ridiculous notions were not taught.

Philippe more or less believed the same thing about evolution as that man who had walked straight out of the Middle Ages, and yet he was ready to wage war against him in the name of civilization. In short, I’m not sure what to do with a belief in God except see it as some form of mental disorder . . .