When the camera is looking back at our planet Earth, it's the tiniest of specks somewhere out there in the universe. So we do have a new sense of proportion. Of course the volcanoes and the magma under us just remind us of that.

There's more substance in my prose and my poetry than in all my films together. Writing is a more direct way of expressing yourself because, in cinema, you always have finances, organization, actors, technical apparatus and all that stuff coming in between.

It's curiosity, and always a sense of poetry. You see it in particular in the chapter "Iceland" where I'm reciting ancient Icelandic poetry. It has this very beautiful gravitas in conjunction with the volcanoes.

This is the birth of the modern human soul. The artists are like us, not like the Neanderthals, who had no culture - and who incidentally were still roaming the landscape at the time the paintings were made. It is striking that there is a distant cultural echo that seems to reach all the way down to us, over dozens of millennia.

With actors, normally I don't like to have any conversation about background and about motivations and all this.

As for the "anger" of the volcano, we leave it up to the local populations who create their demons, their gods and their divine punishment.

I always loved celluloid cameras in the early days that were sturdy and reliable. Even under tropical conditions and downpour of rain, it would still work.