My background educationally is physics and economics, and I grew up in sort of an engineering environment - my father is an electromechanical engineer. And so there were lots of engineery things around me.

Don't be afraid of new arenas.

The lessons of history would suggest that civilisations move in cycles. You can track that back quite far - the Babylonians, the Sumerians, followed by the Egyptians, the Romans, China. We're obviously in a very upward cycle right now and hopefully that remains the case. But it may not.

I hate writing about personal stuff. I don't have a Facebook page. I don't use my Twitter account. I am familiar with both, but I don't use them.

It's important that we attempt to extend life beyond Earth now. It is the first time in the four billion-year history of Earth that it's been possible, and that window could be open for a long time - hopefully it is - or it could be open for a short time. We should err on the side of caution and do something now.

You should be innovating so fast that you're invalidating your prior patents.

When we got Tesla going at the very beginning, if you asked me what I thought the odds of success were, I would have said less than 50%. I would have said that failure is the most likely outcome.