I worked for MI6 in the Sixties, during the great witch-hunts, when the shared paranoia of the Cold War gripped the services.

Completing a book, it's a little like having a baby.... There's a feeling of relief and satisfaction when you get to the end. A feeling that you have brought your family, your characters, home. Then a sort of post-natal depression and then, very quickly, the horizon of a new book. The consolation that next time I will do it better.

I had two experiences of criminality: one was my conman father, the other was teaching at Eton

Look... we're getting to be old men, and we've spent our lives looking for the weaknesses in one another's systems. I can see through Eastern values just as you can see through our Western ones. Both of us, I am sure, have experienced ad nauseam the technical satisfactions of this wretched war. But now your own side is going to shoot you. Don't you think it's time to recognise that there is as little worth on your side as there is on mine?

All power corrupts but some must govern.

The one thing you can bet is that spying is never over. Spying is like the wiring in this building: It's just a question of who takes it over and switches on the lights. It will go on and on and on.

America has entered one of its periods of historic madness, but this is the worst I can remember.