Love this paragraph:

“Musk has been pushing this line – Mars colonisation as extinction insurance – for more than a decade now, but not without pushback…. ‘I think we have a duty to maintain the light of consciousness, to make sure it continues into the future.’ People have been likening light to consciousness since the days of Plato and his cave because, like light, consciousness illuminates. It makes the world manifest. It is, in the formulation of the great Carl Sagan, the Universe knowing itself. But the metaphor is not perfect. Unlike light, whose photons permeate the entire cosmos, human-grade consciousness appears to be rare in our Universe. It appears to be something akin to a single candle flame, flickering weakly in a vast and drafty void.”