Your probability of dying on Mars is much higher than earth. Really, the ad for going to Mars would be like Shackleton's ad for going to the Antarctic: "It's gonna be hard. There's a good chance of death, going in a little can through deep space. You might land successfully. Once you land successfully, you'll be working nonstop to build the base."

The topic of compassion is not at all religious business; it is important to know it is human business, it is a question of human survival.

We have the resources to build room for a trillion humans in this solar system, and when we have a trillion humans, we'll have a thousand Einsteins and a thousand Mozarts. It will be a way more interesting place to live.

I thought about the things that will truly affect humanity. I came up with three: the internet, sustainable energy and space travel.

If humanity doesn't land on Mars in my lifetime, I would be very disappointed.

The future of humanity is going to bifurcate in two directions: Either it's going to become multiplanetary, or it's going to remain confined to one planet and eventually there's going to be an extinction event.