Why Stephen Hawking thinks the Brexit vote could threaten humanity

"Envy and isolationism" were the forces that contributed to the U.K.'s decision to leave the European Union and if those forces grow stronger, the human race is at risk, according to world-renowned physicist Stephen Hawking.

Writing in The Guardian newspaper on Friday, Hawking said that the June 23 vote was down to British attitudes towards wealth and money and that it was time for an "honest" debate about "the role that wealth does and doesn't play in our society."

Hawking had been a part of the remain camp in the lead up to the referendum, saying that it would be a mistake for Britain to leave the union. He had argued that Britain risked being isolated and that crucial funding for scientific research was at risk.

The vote to leave the EU was largely seen as having been driven by concerns over the U.K.'s sovereignty and immigration, although there were widespread regional and socio-economic differences between those voting to leave and those wanting to stay in the EU.

In his opinion piece Friday, Hawking said he was "sad about the result, but if I've learned one lesson in my life it is to make the best of the hand you are dealt."

"Now we must learn to live outside the EU, but in order to manage that successfully we need to understand why British people made the choice that they did," he said, adding that "I believe that wealth, the way we understand it and the way we share it, played a crucial role in their decision."

Although money is important as a "facilitator for ideas, or health, or security," Hawking said, he added that a narrow-definition of wealth and an unwillingness to share had been factors behind the U.K. vote.

He warned that it was "never as an end in itself" and he hoped fundamental assumptions about wealth and ownership would change amid challenging times.

"We are in perilous times. Our planet and the human race face multiple challenges. These challenges are global and serious – climate change, food production, overpopulation, the decimation of other species, epidemic disease, acidification of the oceans. Such pressing issues will require us to collaborate, all of us, with a shared vision and cooperative endeavour to ensure that humanity can survive," he wrote.

"We will need to adapt, rethink, refocus and change some of our fundamental assumptions about what we mean by wealth, by possessions, by mine and yours. Just like children, we will have to learn to share."

The scientist warned that "if we fail, then the forces that contributed to Brexit, the envy and isolationism not just in the U.K. but around the world that spring from not sharing, of cultures driven by a narrow definition of wealth and a failure to divide it more fairly, both within nations and across national borders, will strengthen."

"If that were to happen, I would not be optimistic about the long-term outlook for our species," he added.

Ending on a more positive note, Hawking said: "We can and will succeed. Humans are endlessly resourceful, optimistic and adaptable. We must broaden our definition of wealth to include knowledge, natural resources, and human capacity, and at the same time learn to share each of those more fairly. If we do this, then there is no limit to what humans can achieve together."

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