When you look at the paintings at Chauvet Cave, they're not primitive or like children's little scribbles, it bursts on the scene fully accomplished and when you look through the faces of cultural history, art history, it has never gotten any better.

If you do not have an absolutely clear vision of something, where you can follow the light to the end of the tunnel, then it doesn't matter whether you're bold or cowardly, or whether you're stupid or intelligent. Doesn't get you anywhere.

I must say, the people who started this whole Masterclass series have been very helpful and very intelligent to point out certain things and also give me some guidance, "isn't there something missing, shouldn't we address this or that?" so it's not completely alone out of the blue. It's very well thought through.

I have worked for YouTube like texting and driving because I was curious to test what's out there and how does it function, can I release something like about texting and driving to very young audiences, at the age where they do their drivers test? And the response was phenomenal, millions of people saw it.

There are photos of Kim Jong-un right up atop the volcano. I actually wrote a letter to him asking if I could speak on camera. I never got an answer. But what was interesting was the people who were responsible for us, our "guards," it took them two days to figure out how I should address him. "President? No, you can't because there's a president for eternity." And it was a time when his status was still in flux. Only a few months later there was this party congress which assigned an official title to him, but that was after we did our film.

"Jack Reacher" was easy because the function of the villain was just to spread fear and horror.

I think Irish people started to move to the United States - many things that were of consequence. And it was a tiny and mild event compared to what had happened 74,000 years ago.