Elon Musk says

“I wonder how many dead one-planet civilizations are out there in the cosmos that never made it to the other planet and ultimately extinguished themselves or were destroyed by external factors. Probably a few.”

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“We need to take all heavy industry, all polluting industry, and move it into space. And keep Earth as this beautiful gem of a planet that it is.”

“We’re going to build a road to space so that our kids and their kids can build the future. And we need to do that. We need to do that to solve the problems here on Earth. It’s not about escaping.”

“Humanity has been small. That’s not true anymore. The Earth is no longer big. Humanity is big. Earth seems big to us, but it’s finite.”