We have made remarkable progress in the last hundred years, but if we want to continue, our future is in space.

Although quantum mechanics has been around for nearly 70 years, it is still not generally understood or appreciated, even by those that use it to do calculations.

We are very, very small, but we are profoundly capable of very, very big things.

A model is a good model if first it interprets a wide range of observations in terms of a simple and elegant model, and second if the model makes definite predictions that can be tested, and possibly falsified, by observation.

We live in the most probable of all possible worlds.

The universe is governed by science. But science tells us that we can't solve the equations, directly in the abstract.

Someone told me that each equation I included in the book would halve the sales.