It's not the pessimism that gets me down. It's the optimism; the belief – almost knowledge – that if enough of us got together and cried "No!" in unison, we could change the world. The heady high of giving a radical and rabble-rousing speech to rapturous applause, followed by the crushing low that comes when it's revealed just how few of those people realise that a principle is for life, not just for conference.

My dad is much more pessimistic than I am, and he's much happier for it.