I didn't become leader to transform the Liberal Democrats into an enlarged form of the Electoral Reform Society. It's not the be all and end all for us. There are other very, very key ambitions in politics, not least social mobility and life chances, that I care about as passionately if not more.

I genuinely believe that we will look back on today as a landmark for equality in Britain ... No matter who you are and who you love, we are all equal. Marriage is about love and commitment, and it should no longer be denied to people just because they are gay.

If you scratch below the surface and ask what really makes me tick, it's the liberalism of trying to promote freedom and opportunity. Promoting social mobility is one of the keys to that.

The Liberal Democrats will add a heart to a Conservative government and a brain to a Labour one.

I don't even pretend we can occupy the Lib Dem holier-than-thou, hands-entirely-clean-and-entirely-empty-type stance. No, we are getting our hands dirty, and inevitably and totally understandably we are being accused of being just like any other politicians.

Grown-up politicians talk to each other across party lines. Over the last few weeks I have had lengthy conversations with Ed Miliband, David Miliband, with Tony Blair, with Peter Mandelson... talking about Europe, talking about political reform.

I will not accept a new wave of fiscal retrenchment, of belt-tightening, without asking people at the top to make their contribution, to make an additional contribution. I don't think you can ask people on middle and low incomes, who, after all, are the vast majority of the British population, to bear the brunt of this adjustment.