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Are bilinguals rational? How foreign languages affects the human brain

Updated: Jul 21, 2021

I'm sure there are many readers of this blog who can speak or are learning a foreign language. There are many reasons why people start learning a foreign language. For some, it is an interest in the language and culture of a country, while for others, it is out of necessity.

Being able to speak a second language has many advantages, such as expanding work opportunities, making friends around the world, and feeling comfortable when traveling abroad. However, the advantage I would like to talk about today is that you can be more rational when you think in a second language. While those of us at translation companies use foreign languages daily without considering the significance, in this article, we will introduce the unexpected benefits of using a second language.

Language is tied to emotion and reason

When I was living in China, a friend of mine who spoke Chinese fluently as a second language once performed a Japanese manzai (comic storytelling) show in Chinese at a party in order to entertain Chinese people. He was convinced that the audience would "burst into laughter." He was wrong. The audience all had puzzled looks on their faces during the performance, and it was difficult for my friend to make it through the awkward experience.

On the other hand, from my own experience, even though I had been in China for 10 years, I still could not understand why Chinese people were laughing so hard when they watched "Xiàngsheng," a traditional Chinese comic performance. These two examples illustrate the difficulty of understanding and communicating humor and emotional expressions in a second language.

Language not only serves the function of expressing emotions, but it is also a tool for rational thought. Daniel Kahneman, a Nobel Prize-winning cognitive psychologist in economics, writes in his book "Thinking, Fast and Slow" about "fast thinking" and "slow thinking."

According to Kahneman, we rely on fast thinking to make many decisions in order to live our daily lives comfortably, but this way of thinking tends to lead to biased decisions.

For example, suppose there are two containers of apple juices labeled "90% or more fruit juice" and "10% or less additives," respectively.

Even though they are basically the same, most Japanese people will instantly choose the first container because they have a vague image that "fruit juice = good for you.” This feeling is strongly connected to emotions and can be a bias that distorts our judgment.

Can reason develop in a second language?

While slow thinking is usually more rational, when fast thinking drives us to make decisions in our mother tongue, it can become overbearing, and we make decisions emotionally and instantaneously. And in making these decisions, we cannot avoid the biases associated with familiar cultures and images.

This is where a second language comes in handy. Except for those who have been exposed to more than one language from birth, a person’s second language is generally not as good as his or her mother tongue. Therefore, when trying to think in that second language, people inevitably end up thinking slowly. As a result, the intrusive fast thinking that takes place in the mother tongue disappears, and the rational system is better able to make decisions.

In fact, Alberto Costa, an expert in cognitive functioning, has stated that we make calmer and more rational decisions when we think in our second language than when we think in our first language, a view that has been supported by other studies.

Verbalize your feelings in a second language

In our work and personal lives, we sometimes face situations where we become frustrated and lose our temper. We need to avoid letting our fast thinking take over our brains and doing something we will later regret as a result. In this case, it can be handy to verbalize the situation in a second language.

When feeling overwhelmed by negative emotions, it is said to be effective to “verbalize” your thoughts by writing them down and observing your situation objectively. This can take longer in a second language, and during that time, you may find that you are able to think calmly, and negative emotions will gradually disappear from your mind like a receding tide.

In Japan, it is often said that Chinese and English are logical languages as compared to the Japanese language, which is often viewed as more ambiguous and contextual. However, in addition to the characteristics of each language, this perception could also come from being naturally forced to be more rational when speaking in a foreign language.

Everyone would agree that humans use language, but when you think about how language can make people emotional or rational, doesn't it seem as if language might be manipulating and controlling us? It's a somewhat strange concept, but why don't you try it and see if it's really true?

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Born in Japan, Kawai moved to China in 2008 to study the Chinese language in Chengdu, Sichuan province. Later, he deepened his learning in Hunan and Jiangsu provinces through close interaction with locals. He then spent a year and a half in Ghana, Africa, working to master English and the local language, Tui. Forced to return to Japan due to the COVID-19 pandemic, he now lives in Fukuoka Prefecture, Japan.

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Originally from Ohio, USA. With a background in science and more than 24 years of teaching English around the world, Richard is an excellent editor and copywriter, especially for technical and scientific content.

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