In almost all city governments in America, the small group of people who don't want change are able to block change.

Copenhagen has done a remarkable job creating streets that are focused on bicycles and pedestrians.

I think there's a gigantic generation gap in terms of how people understand the Internet and how much they think technology is an important factor in social change.

Optimism is a political act. Those who benefit from the status quo are perfectly happy for us to think nothing is going to get any better. In fact, these days, cynicism is obedience.

Urban retrofitting: creating different sorts of spaces and uses out of places that are already there.

If mass media, social isolation in the suburbs, alienating workplaces and long car commutes create a bunker mentality, the Internet does the opposite.

By looking at climate change as a clean energy generation problem, we're setting ourselves up not to solve it.

It's not just enough to survive. We've got to make something better than what we've got.

The denser places get, the lower the amount of energy people use to get around it.

We have to craft new political realities, not only in places like India, Afghanistan, Kenya, Pakistan, but here at home as well. Another world is possible.

Cabbies in particular seem to like discussing the fate the Earth.

When life expectancy hit 95 years of age, married people around the world shouted, "Enough!" And just like that, the institution of marriage was reinvented.

Let there be spaces in your togetherness.And let the wind of the heavens dance between you.

Do you have any idea how rare a twenty-three-year-old virgin is where I come from?

We're very good in America at talking about stuff, often stuff to buy. We tend to talk about our iPods. We tend to talk about cars or new fads.

I know he would die if you died, Luce

If my father could watch my son for a while, he might realize his own immortality.

Its just as disappointing as it was thrilling to win the Masters. To come very close, to play so hard for 72 holes and play better than everybody but one guy is disappointing.

Sales = income. The reason so many people have low incomes is that they are poor at selling.

If we measured success by longevity, then dinosaurs must rank as the number one success story in the history of land life.

Many are destined to reason wrongly; others, not to reason at all; and others, to persecute those who do reason.