Aeon

‘At our current rate of technological growth, humanity is on a path to be godlike in its capabilities,’ Musk told me. ‘You could bicycle to Alpha Centauri in a few hundred thousand years, and that’s nothing on an evolutionary scale. If an advanced civilisation existed at any place in this galaxy, at any point in the past 13.8 billion years, why isn’t it everywhere? Even if it moved slowly, it would only need something like .01 per cent of the Universe’s lifespan to be everywhere. So why isn’t it?’

Musk has a more sinister theory. ‘The absence of any noticeable life may be an argument in favour of us being in a simulation,’ he told me. ‘Like when you’re playing an adventure game, and you can see the stars in the background, but you can’t ever get there. If it’s not a simulation, then maybe we’re in a lab and there’s some advanced alien civilisation that’s just watching how we develop, out of curiosity, like mould in a petri dish.’ Musk flipped through a few more possibilities, each packing a deeper existential chill than the last, until finally he came around to the import of it all. ‘If you look at our current technology level, something strange has to happen to civilisations, and I mean strange in a bad way,’ he said. ‘And it could be that there are a whole lot of dead, one-planet civilisations.’