Between building self-driving cars, spaceships and tunnels, Elon Musk has been thinking about artificial intelligent smarter than humans, alien life contacting Earth and dying on Mars.
Barely a week goes by without the Tesla and SpaceX boss dreaming up a new plan which borders on science fiction, so it was perhaps inevitable that his attention would soon turn to alien life.
Speaking at the World Government Summit in Dubai on 13 February, Musk said a "super" form of artificial intelligence (AI), far smarter than the most intelligent human, would be developed in years rather than decades.
But greater intelligence poses a concern for Musk. "One of the most troubling questions is AI. I don't mean narrow AI like vehicle autonomy, where it is narrowly trying to achieve a simple function. But deep AI, or what is known as general AI, where you can have AI that is much smarter than the smartest human on Earth. This I think is a dangerous situation."
Developing this form of 'digital superintelligence' within the next "10 to 20 years" will be like being visited by an alien, Musk said.
Shifting gears to consider the probability of alien life, Musk went on: "I think this is one of the great questions in physics and philosophy. Where are the aliens? Maybe they are among us I don't know. Some people think I'm an alien. I'm not, but of course I'd say that wouldn't I?"
'We are not smart enough to realise aliens are watching us'
Musk added: "If there are superintelligent aliens out there then they probably are observing us. That would seem quite likely, and we are just not smart enough to realise it." By applying some "back-of-an-envelope calculations", Musk reasoned it would be "nothing in the grand scheme of things" for an alien civilisation to populate the entire galaxy in 10 million to 20 million years.
Speaking of being a multi-planetary species, as Musk wants humans to be, he was asked about him famously wanting to die on Mars. "We're all going to die someday and if you're going to pick some place to die, then why not Mars? If we are born on Earth, why not die on Mars? Seems like maybe it'd be quite exciting.
"I think, given the choice of dying on Earth or dying on Mars, I'd say yeah sure, I'll die on Mars. But it's not some kind of Mars deathwish. And if I do die on mars, I just don't want it to be on impact."
Musk also used his speech in Dubai to remind us of his plans for intertwining humans brains with computers in what is known as a neural lace. "Over time I think we will probably see a closer merger of biological intelligence and digital intelligence," he said. "It's mostly about the bandwidth, the speed of the connection between your brain and the digital version of yourself".
Musk recently tweeted to say he was "making progress" on the brain/computer interface, and said he would make an announcement "maybe" in February 2017.