What if I tell you that a person does not think in the same way in his/her mother tongue and in a foreign language? Is it possibile to end up making a decision instead of another merely based on the language used in the conversation leading to such a choice? The answer is yes!

Such a phenomenon is called the Foreign Language Effect and can be wonderfully summarised with Mandela’s words:

As a matter of fact, recent studies suggest that the language you speak may surprisingly influence your moral judgement and, in particular, emotions may prevail in the mother tongue, whereas a foreign language makes you think coldly and far more rationally. In other words, Mandela was right! The reasons behind such a phenomenon might by several, for example, this might be a reflection of different cultural values or it may be due to the increased emotional distance that one experience while speaking a foreign language.

As widely known in psychology, the decision-making process is mostly monopolised by the amygdala, which controls our emotions. And the truth is that, despite the huge amount of rational data we are constantly bombarded with, it’s our emotions that lead us to make the decisions we finally make.

Pragmatically speaking, what does the Foreign Language Effect imply? Among others, that in a trade negotiation using the mother tongue of the person you want to make a deal with gives you leverage. This was, in fact, Mandela’s strategy in his secret meetings with de Klerk. But what if you don’t speak that language? Then you have two options:

• hiring an interpreter, who will turn the “Mother Tongue Effect” in your favour and you’ll be more likely to achieve the deal;

• using a lingua franca, such as English. This might be indeed a cheaper solution, but also a counterproductive one, especially if your rhetoric skills —which are fundamental in a negotiation— in English aren’t that persuasive. On top of that, the Foreign Language Effect is playing against you, don’t forget it! This is the strategy recommended by Willy Brandt, who said:

If I am selling to you, I speak your language. If I am buying, dann müssen sie Deutsch sprechen.” 

This is a very brief and coincise summary. If you’re interested in the studies behind this theory and want to read more, here are the reference sources:

• Keysar, B., Hayakawa, S., & Sun Gyu, A. (2012). The foreign language effect: Thinking in a foreign tongue reduces decision biases. Psychological Science, 23, 661–668
• Tversky, A., & Kahneman, D. (1981). The framing of decisions and the psychology of choice. Science, 211(4481), 453–458
• Costa A., Foucart A., Arnon I., Aparici M. & Apesteguia J. (2014). “Piensa” twice: On the foreign language effect in decision making, Cognition, 130 (2) 236-254. DOI: 10.1016/j.cognition.2013.11.010
• International Journal of Psychophysiology: Emotion and lying in a non-native language
• Neuropsychologia: Emotionality in a second language: it’s a matter of time
• PLOS ONE: Your Morals depend on the language
• Divulgame.org: Mandela tenía razón: el Efecto de la Lengua Extranjera
• Guardian Liberty Voice: Moral Judgment Influenced by What Language You Speak