Anyone who has wrestled knows that it's the hardest thing in the world to do. Anyone who says something else is the hardest thing has never wrestled. That's what I have found. ... You don't wrestle because it's easy, you wrestle because it's hard. I don't do astrophysics because it's easy, I do it because it's hard. And I juxtapose the two in my mind, body, and soul all the time.

Like no other science, astrophysics cross-pollinate s the expertise of chemists, biologists, geologists and physicists, all to discover the past, present, and future of the cosmos-and our humble place within it.

I try to keep this in mind when tied in to a rope 75 feet up in a tree... The history of ideas about our place in the universe has been a long series of let-downs for those who like to believe we are special.

My only hope is that every other alien civilization isn't doing exactly what we are doing because then everybody would be listening, nobody would be receiving, and we would collectively conclude that there is no other intelligent life in the universe.

Give a kid a book, and you change the world. In a way, even the universe.

A scientist is just a kid who never grew up.

But to measure cause and effect... you must ensure that a simple correlation, however tempting it may be, is not mistaken for a cause. In the 1990s the stork population of Germany increased and the German at-home birth rate rose as well. Shall we credit storks for airlifting the babies?