No surprise: Senator Bernie Sanders had a lot to say about Wall Street at last night’s Democratic primary debate.

“Too much economic power, too much political power, and the economists that I talk to say we should break them up,” he said.

In a previous debate in January, he talked about the importance of appointing the right people to economic policy positions: ”If you have an administration stacked with Wall Street appointees, it ain’t going to accomplish very much.”

But despite repeated inquiries, Sanders’ campaign won’t tell Quartz, or anyone else, which economists he is talking to, or who he plans to appoint to high-level positions if he becomes president. What kind of experience does he think is is relevant, beyond not working in the financial sector? No one knows.

“I’m not going to get ahead of the senator on that,” said campaign press secretary Symone Sanders after last night’s debate. If not now, when? Sanders has been running for president for eight months, and voting has already begun.

It’s true that Sanders name-checks progressive economists. He told the Hill newspaper in October that he considered the Nobel prize-winning economists Paul Krugman and Joseph Stiglitz important influences. But Krugman has been critical of Sanders’ plans for healthcare and financial reform, while Stiglitz is also claimed as an adviser by Sanders’ rival, Hillary Clinton. Update, 2/7/16: Asked about his work on political campaigns, Stiglitz relayed to Quartz that he spoke with Clinton’s campaign staff several times in 2015.

Sanders has also name-checked Senator Elizabeth Warren for her support of reinstating Glass-Steagal, a law that once separated commercial and investment banking, but Warren has also praised Clinton’s financial regulation proposals.

At least one Sanders economic adviser is on record: Gerald Friedman, a UMass-Amherst economic historian, wrote a cost analysis of Sanders’ single-payer health care plan that was shared with reporters by the campaign. That analysis has been questioned by other experts, who say it significantly over-estimates revenue and cost-savings in the plan.

That kind of back and forth may be what the campaign is trying to avoid by staying mum on where Sanders gets his ideas. But even more than critics, his supporters should be demanding more transparency—and the reason is Barack Obama.

Obama ran as a outsider against Clinton in 2008, and was critical of her centrist economic views. But when he took office and faced hundreds of appointments to economic policy jobs in the midst of a crisis, Obama called mostly on Democratic wonks holed up in think tanks, law firms, universities, and, yes, Team Clinton. It shouldn’t be too surprising that a Democratic president went to his party’s establishment to fill out his administration, but it definitely disappointed progressive voters.

Who will Sanders appoint as Treasury secretary or SEC chairman when he is president in order to implement his heralded political revolution? Maybe he will pull an Obama and appoint the usual Democratic Party suspects. Perhaps, like Franklin Delano Roosevelt with his New Deal brains trust, Sanders will elevate a cadre of relatively unknown academics and lawyers to implement big reforms. But FDR’s advisers were already part of a progressive movement that urged the government to use science and economics to better the lives of its citizens. If Sanders has a brains trust, we haven’t met them yet.