My dad, Donald, was a vet and had a practice in Yorkshire. Cats and dogs were his bread and butter, but his greatest love was large animals.

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.

Failure, it is thought, is what sells, and what people want to hear and read about. I am not so sure.

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.

By asking the question 'Am I happy?,' and via the answer setting out what I mean by happiness, there is a political route that can be taken, by asking another question - 'Can politics deliver happiness, and should it try?'

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.

To me, marriage is partly a religious thing and I'm not religious.

By asking the question 'Am I happy?,' and via the answer setting out what I mean by happiness, there is a political route that can be taken, by asking another question - 'Can politics deliver happiness, and should it try?'

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.

There has been a shift to what may be defined as a culture of negativity which goes well beyond coverage of politics.