For all its material advantages, the sedentary life has left us edgy, unfulfilled, even after 400 generations in villages and cities, we haven't forgotten: The open road still softly calls like a nearly forgotten song of childhood.

When you look more generally at life on Earth, you find that it is all the same kind of life. There are not many different kinds; there's only one kind. It uses about fifty fundamental biological building blocks, organic molecules.

It means nothing to be open to a proposition we don't understand.

We are not smart enough to decide which pieces of knowledge are permissible and which are not.

There are wonders enough out there without our inventing any.

The desire to be connected with the cosmos reflects a profound reality, but we are connected; not in the trivial ways that astrology promises, but in the deepest ways.

Philosophers and scientists confidently offer up traits said to be uniquely human, and the monkeys and apes casually knock them down -- toppling the pretension that humans constitute some sort of biological aristocracy among the beings on Earth.