I'm as skeptical as anyone would be about celebrities and causes - and I will dare to say to you that I don't think of myself as a celebrity per se.

I'm a singer, not a politician, and I think you don't want the two to get confused. It's not OK to be on CNN talking about people starving and then tell the interviewer that your new album is coming out in six months.

There was a moment when Prince did rock & roll with a sponge-y seductive sound. I think that's what was in our head for 'Get On Your Boots.' But actually, the song is much more punk rock.

I think carrying moral baggage is very dangerous for an artist. If you have a duty, it's to be true and not cover up the cracks.

It's much easier to be successful than it is to be relevant. The tricks won't keep you relevant. Tricks might keep you popular for a while, but in all honesty, I don't know how U2 will stay relevant. I know we've got a future. I know we can fill stadiums. And yet with every record, I think, 'Is this it? Are we still relevant?'

Marriage is this grand madness, and I think if people knew that, they would perhaps take it more seriously.

Happy the country that lives on nothing but its wits; cursed be the one that thinks it can get rich by planting or digging or drilling for wealth.

Actually oddly enough, I think my work, the activism, will be forgotten. And I hope it will. Because I hope those problems will have gone away.

Hanging out with politicians and corporations is very unhip work. But I think that the U2 audience have turned out to be incredibly subtle in their understanding.