(Illustration for the Washington Post)

One thing we definitely won’t be hearing out of Mitt Romney’s mouth in his much-anticipated acceptance speech at this week’s convention is anything spoken in French. It’s been the odd subject of primary-season ridicule, as well as attack ads from the left, that the candidate has — wait for it — good foreign language skills. Quelle horreur!

But a post from last week’s Harvard Business Review blog got me thinking: Can speaking a foreign language make you a better leader?

The HBR piece reports on a recent conference on global leadership, and notes findings that “sensitivity to culture” or “cultural empathy” ranks first among all of the critical soft skills that make great global leaders. And the best way to achieve this is to learn other languages, which far fewer Americans than Europeans do. “Since every business professional around the world has (happily for them) been taught to communicate well in English, American business students simply — and arrogantly — assume that they don’t need to bother with learning” a second language, writes HBR’s Bronwyn Fryer.

Beyond cultural sensitivity, however, or the ability to impress foreign officials or executives, how else might a second language help leaders? I went looking for evidence.

The Economist and Wired highlighted a recent study from the journal Psychological Science, which found that thinking in a foreign language helps people to avoid common cognitive traps. In a series of studies, a group of psychologists found that thinking in another language reduced the misleading biases people hold that influence how we weigh the risks and benefits in a decision. Given how critical decision-making is in every leadership job, and how easy it is for anyone to fall into the trap of letting biases lead their thinking, perhaps a second language should be more of a resume booster than just the potential for an executive to win business overseas.

Another recent study from the Proceedings of the National Academy of Sciences showed that Northwestern University researchers had, for the first time, discovered differences in how bilingual thinkers process the sounds of speech. That seems to improve attention and working memory among foreign-language speakers: “because you have two languages going on in your head, you become very good at determining what is and is not relevant,” Northwestern professor Dr. Nina Kraus told the Wall Street Journal. “You are a mental juggler.” Few would argue that a more focused brain able to juggle multiple demands is a great leadership trait.

And earlier this year, the New York Times summarized the evidence that bilingualism makes one smarter. In a nutshell, wrote Science staff writer Yudhijit Bhattacharjee, “the bilingual experience improves the brain’s so-called executive function — a command system that directs the attention processes that we use for planning, solving problems and performing various other mentally demanding tasks. These processes include ignoring distractions to stay focused, switching attention willfully from one thing to another and holding information in mind — like remembering a sequence of directions while driving.” If a second language improves the executive function of the brain, wouldn’t it also enhance the executive qualities in a leader?

With all that evidence, why do we knock a foreign language skill in a presidential candidate? Is it simply because the language is French? Or are we skeptical of leaders or potential leaders who boast they can speak another language? Neither really matters. What’s important is not whether a president or executive can conduct foreign relations or lead meetings in another tongue, but how knowing that second language improves their decision-making, mental acuity and problem-solving skills.

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