In his Harvard commencement speech on Thursday, Facebook CEO Mark Zuckerberg advocated exploring a system in which all people receive a standard salary just for being alive, no questions asked.

The system, known as universal basic income, is one of the trendiest economic theories of the past few years. Experiments in basic income have popped up in Kenya, the Netherlands, Finland, Canada, and San Francisco, California, among other places.

Basic-income advocates say the changing nature of work – from human labor to artificially intelligent robots – combined with rising wealth inequality signal the need for an overhaul of how money is distributed.

“We should have a society that measures progress not just by economic metrics like GDP, but by how many of us have a role we find meaningful,” Zuckerberg told the crowd. “We should explore ideas like universal basic income to make sure everyone has a cushion to try new ideas.”

The statement was Zuckerberg’s first public endorsement of the idea, which makes him somewhat late to the party, as far as Silicon Valley goes. Tech executives like Tesla CEO Elon Musk, Y Combinator President Sam Altman, and Facebook cofounder Chris Hughes – who runs a basic-income fund called the Economic Security Project – have endorsed basic income.

Many point to economic forecasts that say robots will displace much of the human workforce in the coming decades. A report from Oxford University in 2013, for instance, found that about 50% of jobs could be taken over within the next 10 to 20 years. A McKinsey report released in 2015 backed up that prediction, suggesting that today's technology could feasibly replace 45% of jobs right now.

"As our technology keeps on evolving, we need a society that is more focused on providing continuous education through our lives," Zuckerberg said. "And yes, giving everyone the freedom to pursue purpose isn't going to be free. People like me should pay for it, and a lot of you are going to do really well, and you should, too."

Watch the commencement address, starting at 1:38:12: