Constantly seek criticism. A well thought out critique of what you're doing is as valuable as gold

In order for us to have a future that's exciting and inspiring, it has to be one where we're a space-bearing civilization.

I would like to fly in space. Absolutely. That would be cool. I used to just do personally risky things, but now I've got kids and responsibilities, so I can't be my own test pilot. That wouldn't be a good idea. But I definitely want to fly as soon as it's a sensible thing to do.

There's a tremendous bias against taking risks. Everyone is trying to optimize their ass-covering.

Physics is a good framework for thinking. ... Boil things down to their fundamental truths and reason up from there.

The revolutionary breakthrough will come with rockets that are fully and rapidly reusable. We will never conquer Mars unless we do that. It'll be too expensive. The American colonies would never have been pioneered if the ships that crossed the ocean hadn't been reusable.

It is definitely true that the fundamental enabling technology for electric cars is lithium-ion as a cell chemistry technology. In the absence of that, I don't think it's possible to make an electric car that is competitive with a gasoline car.