Cities are the greatest creations of humanity.
Winning a competition in architecture is a ticket to oblivion. It's just an idea. Ninety-nine per cent never get built.
I don't get to sleep when I'm in New York. Really. I'm living on adrenaline.
It's been hard to hand over the working design of Freedom Tower to another architect - although we're still a part of the team, and so is Larry.
I'm not Candide, nor Dr Pangloss, but we know that faith moves mountains.
And it is very moving because one has to see the site not as just another site of development but it is a very special site. It is a site that souls and hearts of all Americans.
And you have to remember that I came to America as an immigrant. You know, on a ship, through the Statue of Liberty. And I saw that skyline, not just as a representation of steel and concrete and glass, but as really the substance of the American Dream.
And, yes, I love the process of building.
And then, build a bustling wonderful city of the 21st century, with a restoration of a spectacular skyline, which Manhattan, of course, needs. So, that is really the design as a whole.
I think there is a new awareness in this 21st century that design is as important to where and how we live as it is for museums, concert halls and civic buildings.
We will work with everybody for the good of New York.
There are more people living in Lower Manhattan now than before the terrorist attacks. That's faith for you. There's such a strong spirit here.
The foreign press seems obsessed with the Freedom Tower, as if it was the only thing going on here. In fact, we're trying to keep a huge juggling act in balance, with the tower as just one of the many balls in play.
There will be a competition for the memorial. And then it can be developed with trees, with planting. It can become a very beautiful place protected from the streets, because it is below. And it can be something very moving and very private.
It's a fantastic responsibility and a wonderful moment.
It's about how to bring together the seemingly contradictory aspects of the memorial, which is about a tragedy and how it changed the world, but also about creating a vital and beautiful city of the 21st century.
But the US is a democracy, and when a government is voted out, these humanist notions of life, liberty and the pursuit of happiness continue.
I studied architecture in New York. So, really I was very moved, like everyone else, to try to contribute something that has that resonance and profundity of it means to all of us.
Well, I think one doesn't really have to invent this memorial space, because it is already there. And it is speaking with a voice and, you know, 4 million of us came to see the site.
When you're a kid with artistic yearnings brought up in the Bronx, you don't get fed up too easily.
Well, I didn't want to have the reminder sort of in the sky, so that people would forever look at it. I wanted to have - really to create a city from the bottom up. From that foundation, which held, from the democratic power of what the site really is.
And of course I like Berlin a lot. It's such an interesting city.
Only through acknowledgment of the erasure and void of Jewish life can the history of Berlin and Europe have a human future.
It's a project that touched me as an immigrant and as a New Yorker.
We all came to see that site. We all walked around it. It is already sacred.