The language you speak has far, far more impact on the way you think than you probably are even aware of. It helps you internalise your thinking and make sense of your experiences. You can reflect on things that just happened and analyse the past to learn and grow, and also can comprehend that a future exists and begin to understand how it could pan out.
It alters your perception of literally the tiniest experiences, and I mean not just knowing language, but people who speak different languages think differently because of the way their brain processes information. Also being outside of human contact would mean zero social skills and missing out in probably 99.9% of the learning needed to exist in modern society.
Humans learn mainly through social experiences and observing others first, especially during formative years, either their parents, siblings, peers, strangers in the street, characters on TV etc.
The human brain has a huge capacity for learning, but it can’t do it without some sort of facilitation. When we learn, the brain actually PHYSICALLY changes in shape, known as neuroplasticity.
I could go on about this topic for hours. My degree is in Education Studies and I wrote my dissertation on second language learning.
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