Billionaire investor Warren Buffett is once again wading into the topic of politics.
Buffett, who supported Democrat Hillary Clinton in the 2016 presidential election and has previously weighed in on whether or not executives like Michael Bloomberg or former Starbucks CEO Howard Schultz would make good candidates, said in a recent interview that there is one question he would want to ask the field of candidates planning to run for the White House in 2020.
"I want to hear what they tell people who disagree with them," Buffett told Yahoo Finance on Monday. "I would like to ask a candidate: 'What are you for that the majority of your followers are against?'"
That's the best way to be sure that a candidate really believes in a particular issue, according to Buffett. "That's really the test," he says in the interview.
Those comments from Buffett came in response to a question about whether the billionaire would ever ask a candidate what they think about the economy or other issues. Buffett laughs and points out that any candidate would probably just "tell me what I want to hear" to win his support, which is not what the billionaire would want.
For Buffett, being strong-minded but having enough respect to hear out someone with a different opinion or point of view is a positive thing.
"Charlie, he's given me a lot of good advice over time," Buffett told CNBC in a 2016 interview. "And, I may hate to take it to a certain degree, but sometimes — but my decisions have been better. I've lived a better life because of Charlie."
Billionaire Ray Dalio also thinks listening to those who disagree with you is essential. It's a hallmark of the culture that Dalio has created at his hedge fund, Bridgewater Associates, which he calls "radical transparency."
"I just wanted to see things through [employees'] eyes and to have them see things through my eyes so that together we could hash things out to discover what's true," Dalio said.
Billionaire tech entrepreneur Peter Thiel also likes to ask a question similar to Buffett's question when interviewing job candidates: "What important truth do very few people agree with you on?"
The question is more difficult to answer than you might think, Thiel writes in his book, "Zero to One," as it requires candidates to show both creative-thinking skills as well as the courage to voice an unpopular opinion.
"It's intellectually difficult because the knowledge that everyone is taught in school is by definition agreed upon," according to Thiel. "And, it's psychologically difficult because anyone trying to answer must say something she knows to be unpopular."
Meanwhile, Buffett identifies Vermont Senator Bernie Sanders as one presidential candidate who would not be afraid to answer Buffett's question about unpopular views he holds. Buffett tells Yahoo Finance that Sanders' followers see him as "authentic," adding: "if you asked him what he was for, that most people might be against, he would tell you."
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This story has been updated to include information on Thiel's interview question.