So here is one of my theories on happiness: we cannot know if we have lived a truly happy life until the very end. This view of life and death was reinforced by my close witnessing of the buildup to the death of Philip Gould. Philip was without doubt my closest friend in politics. When he died, I felt like I had lost a limb.

My aunty says I'm the double of my father. He was a workaholic, which I've definitely inherited. And like me, he could be the life and soul of the party, but also quite withdrawn.

He [Tony Blair] was always ambivalent about the [Rupert] Murdoch papers. But he gave other papers the chance to believe it was just about 'The Independent.' And that was wrong.

May I share with you my earliest memory of a political row? It was with my mother, about the Queen - classic Freudian stuff, shrinks would say. I was eight, and refusing to watch the Queen's Christmas Day broadcast.

I have a nightmare about Tony [Blair] and Gordon [Brown] killing each other. Not every month, but now and then. I also have a recurring dream about losing.

What concerns me is that the Independent is going, and there are job cuts at the Guardian, but the wretched Daily Mail is still rampant, making lots of money by millions of people clicking on pictures of cellulited women. I think that's sad.

Friends have suggested that I am the least qualified person to talk about happiness, because I am often down, and sometimes profoundly depressed. But I think that's where my qualification comes from. Because to know happiness, it helps to know unhappiness.