There’s no one I’ve interviewed on the subject of Bruce Rauner—well, maybe Karen Lewis, who called him a “menace to society”—who expressed more disdain for the Republican candidate for Illinois governor than Diane Ravitch. Ravitch, 76, a research professor of education and education historian at NYU, is arguably the country’s foremost left-leaning education expert. She gave me an interview last May from her bed at a rehab center—recuperating from knee replacement surgery—for my profile of the private equity multimillionaire and devoted education reformer who has an admirable record of pouring his own money into both CPS schools and charter schools.

Ravitch described for me her trip to Chicago in 2011 to receive the Kohl Education Award, given annually by philanthropist Delores Kohl to honor outstanding teachers. That evening, Kohl hosted a small dinner at the Chicago Club. There were two tables of eight, and at one of them Rauner and Ravitch were seated across the table from each other. “We were dominating the conversation,” Ravitch told me, “debating charters.”

The conversation, necessarily loud because they weren’t seated next to each other,  went as follows (Ravitch admits she’s paraphrasing because she didn’t tape the back and forth):

Ravitch: It doesn’t seem fair that charters can exclude students with disabilities.  That leaves them to public schools. 

Rauner: That’s no problem for us. Kids who don’t speak English, we don’t have to take them. 

Ravitch: That’s not fair.

Rauner: What’s wrong with not taking kids? We don’t need kids whose families are not highly motivated. That’s our choice.

(When asked about the dinner, the Rauner campaign did not address the exchange but said in an emailed statement, “The Rauners’ greatest passion is education, and they have spent years trying to improve educational outcomes for students by supporting charter, choice, and traditional public schools.”)

“It’s a terrible idea to elect Rauner governor,” Ravitch told me. “Hedge fund managers [again, Rauner’s business is private equity] love charters….  It’s one thing if a rich guy gives money to charters, but quite another if this guy becomes governor of a big state.” She added,  “In my opinion, charter schools represent a new kind of dual system…. Long-term, it’s not a vision for American society.”

Ravitch—an assistant secretary of education in the George H.W. Bush's education department and counselor to his secretary of education, Lamar Alexander who, in 2010, switched sides from being a conservative on education issues to a liberal—also blogged about the same encounter with Rauner. She accurately described Rauner as “….one of the most important financial backers of charter schools in Chicago. He even has a charter school named for him, part of the Noble network of charters.”

She didn’t intend those facts as a compliment. Politico magazine described her as having concluded that her previous positions were mistaken:  “….charter schools weren’t significant outperforming public schools” and “test-based accountability… punished worthy teachers.”

She told Salon’s Josh Eidelson that public schools will soon disappear from the American urban landscape. “Why destroy public education,” she said, “so a handful can boast they have a charter school in addition to their yacht?”  (Presumably she was not referring to Rauner here because while we know he owns lots of expensive stuff, he doesn’t appear interesting in yachting.)

Former CPS superintended Jean-Claude Brizard, who admires Rauner, told me that he didn’t witness the exchange but heard it was “quite awkward…. I don’t think he’s cold-hearted, it’s more that he’s blunt. I’m familiar with that personality…. These are people who tell you what they think.”

Karen Lewis and Diane Ravitch have become friends. Ravitch is now an ardent supporter of the right of teachers unions to organize and strike. She describes the Lewis-led 2012 Chicago strike as a big success: “It showed the teachers, at least in one city,” she told Salon’s Eidelson, “were not going to lie down and allow their kids to be in an overcrowded classroom with no arts, no library, and a lot of things they didn’t have that Rahm Emmanuel’s [sic] kids expect as part of their schooling.”