With an estimated net worth of $75 billion, Bill Gates, the richest person on Earth, would need to add another $925 billion to his fortune before becoming the first trillionaire in history. As implausible as it may sound, one Silicon Valley entrepreneur believes such an achievement isn’t just doable, but over the next several decades, inevitable — and it won’t necessarily be Gates who gets there. “We need to be ready for a world with trillionaires in it,” says Sam Altman, the president of Y Combinator, the tech industry’s largest and most well-respected incubator for start-ups. “And that’s always going to feel deeply unfair. It feels unfair to me. But to drive society forward, you’ve got to let that happen.” Altman’s hunch is a solid one. Bob Lord, an inequality analyst and tax attorney, believes the shift in wealth could happen as early as 25 to 30 years from now. But it probably won’t be someone like Gates who makes it to 13 digits first — Gates is far too preoccupied with giving his money away, Lord says. “I think it’s going to take someone less like Gates and more like Rockefeller,” he tells Tech Insider.