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

The Spy Who Came in from the Cold was the work of a wayward imagination brought to the end of its tether by political disgust and personal confusion. Fifty years on, I don't associate the book with anything that ever happened to me, save for one wordless encounter at London airport when a worn-out, middle-aged military kind of man in a stained raincoat slammed a handful of mixed foreign change on to the bar and in gritty Irish accents ordered himself as much Scotch as it would buy. In that moment, Alec Leamas was born. Or so my memory, not always a reliable informant, tells me.

Thank heaven, though, one of the few mistakes I haven't made is to talk about the unwritten book.

Smiley was soaked to the skin and God as a punishment had removed all taxis from the face of London.

If you see the world as gloomily as I see it, the only thing to do is laugh or shoot yourself.

I think that where I've watched a movie go wrong, it's usually because the dread committee has been interfering with it.

I have a theory which I suspect is rather immoral,' Smiley went on, more lightly. 'Each of us has only a quantum of compassion. That if we lavish our concern on every stray cat, we never get to the centre of things.