We prefer synthetic rather than natural materials. Natural products are almost too valuable. Wood is much harder to produce than metal. And metal is recyclable, while wood isn't.

Transparency is not the same as looking straight through a building: it's not just a physical idea, it's also an intellectual one.

Critics are entitled to have an opinion, but how can they judge how comfortable a building is? No critic is smart enough to judge how a building will perform over time.

I've never looked at a suburban building as being a minor building and an urban building as being a major building.

You'd never think of taking a cab if you had to walk a mile down Chicago's Michigan Avenue. But in a bad city you take a cab just to go around the corner.

You don't know what the Chinese expect in the way of beauty. The presentation is just a farce. You come into a room filled with 50 people and they don't talk to you. There's very little interaction.

A good engineer thinks in reverse and asks himself about the stylistic consequences of the components and systems he proposes.