Bill Gates rebuked proposals, floated over the last two days by leaders like Donald Trump, to reopen the global economy despite the Covid-19 coronavirus outbreak, saying that this approach would be “very irresponsible.”

Gates did not mention Trump by name, but the American president has said that he may decide to relax some of the country’s “social distancing” in order to jumpstart the country’s shut-down economy. Gates, the country’s leading philanthropist, has been among the most active tech leaders in using his resources to try and contain the virus.

“There really is no middle ground, and it’s very tough to say to people, ‘Hey, keep going to restaurants, go buy new houses, ignore that pile of bodies over in the corner. We want you to keep spending because there’s maybe a politician who thinks GDP growth is all that counts,’” Gates said in an interview with TED Tuesday. “It’s very irresponsible for somebody to suggest that we can have the best of both worlds.”

Trump has suggested that this middle ground would indeed be possible — by letting some healthy people return to work, for instance, while keeping more vulnerable workers in their homes. Experts have said that drastic and widespread social distancing is required to keep the pandemic from spreading further. Trump has said he would make a decision at the end of the month but has said that he believes the “cure” could be worse than the “problem itself.”

Asked what he would do if he were president, Gates returned to his concerns about reopening the economy.

“The economic effect of this is really dramatic. Nothing like this has ever happened to the economy in our lifetimes,” Gates said. “But bringing the economy back ... that’s more of a reversible thing than bringing people back to life. So we’re going to take the pain in the economic dimension — huge pain — in order to minimize the pain in the diseases-and-death dimension.”

The Bill and Melinda Gates Foundation has put up $100 million for programs to fund testing and science around the pandemic, and he has begun using his public profile, too, to shape the coronavirus conversation. This month, Gates himself resigned from the board of Microsoft, which he founded, and is now effectively a full-time philanthropist — and the country’s most famous one.

And Gates has tried to cast himself as an optimist. He has said that the social distancing measures might need to last as little as six weeks, but said that “we have no choice,” despite the economic impacts.

“It’s disastrous for the economy,” Gates said. But “the sooner you do it in a tough way, the sooner you can undo it and go back to normal.”