You need to be in the position where it is the cost of the fuel that actually matters and not the cost of building the rocket in the first place.

You could power the entire United States with about 150 to 200 square kilometers of solar panels, the entire United States. Take a corner of Utah... there's not much going on there, I've been there. There's not even radio stations.

There are really two things that have to occur in order for a new technology to be affordable to the mass market. One is you need economies of scale. The other is you need to iterate on the design. You need to go through a few versions.

I think it's important to reason from first principles rather than by analogy. The normal way we conduct our lives is we reason by analogy. [With analogy] we are doing this because it's like something else that was done, or it is like what other people are doing. [With first principles] you boil things down to the most fundamental truths…and then reason up from there.

You shouldn't do things differently just because they're different. They need to be... better.

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.

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.