Biophysicist and author Stefan Klein wants to ensure the future of German as a language of science. Our academic language is on the verge of atrophy, he says.
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Anyone who only encounters scientific research in a foreign language pays a heavy price, even if he is a master of the idiom. "We are dumber in English" – this was the conclusion that researchers came to in Sweden and the Netherlands, where children were introduced to English on their first day of school. Lectures in English are part of every subject, but nevertheless, the test results are about ten percent lower on average than in courses taught in the mother tongue. In English seminars, students ask and answer fewer questions; they give the overall impression of being somewhat more helpless. Neither students nor teachers are generally aware of the problem, because they all overestimate their expertise in English.

The entire article is interesting.