An article from PRI (Public Radio International, Minneapolis based organization) explains "how English become the language of science?". It has some interesting unknown/forgotten points.
Full text : http://www.pri.org/stories/2014-10-06/how-did-english-become-language-science
Full text : http://www.pri.org/stories/2014-10-06/how-did-english-become-language-science
If you look around the world in 1900, and someone told you, ‘Guess what the universal language of science will be in the year 2000?’ You would first of all laugh at them because it was obvious that no one language would be the language of science, but a mixture of French, German and English would be the right answer, said Michael Gordin.
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Gordin says that English was far from the dominant scientific language in 1900. The dominant language was German.
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“So the story of the 20th century is not so much the rise of English as the serial collapse of German as the up-and-coming language of scientific communication,” Gordin said.
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After World War I, Belgian, French and British scientists organized a boycott of scientists from Germany and Austria. They were blocked from conferences and weren't able to publish in Western European journals.
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The second effect of World War I took places across the Atlantic in the United States. Starting in 1917 when the US entered the war, there was a wave of anti-German hysteria that swept the country.
“At this moment something that’s often hard to keep in mind is that large portions of the US still speak German,” Gordin said.
In Ohio, Wisconsin and Minnesota there were many, many German speakers. World War I changed all that.
“German is criminalized in 23 states. You’re not allowed to speak it in public, you’re not allowed to use it in the radio, you’re not allowed to teach it to a child under the age 10,” Gordin explained.
The Supreme Court overturned those anti-German laws in 1923, but for years that was the law of the land. What that effectively did, according to Gordin, was decimate foreign language learning in the US.
“In 1915, Americans were teaching foreign languages and learning foreign languages about the same level as Europeans were," Gordin said. "After these laws go into effect, foreign language education drops massively. Isolationism kicks in in the 1920s, even after the laws are overturned and that means people don’t think they need to pay attention to what happens in French or in German."
This results in a generation of future scientists who come of age in the 1920s with limited exposure to foreign languages.
That was also the moment, according to Gordin, when the American scientific establishment started to take over dominance in the world.
“And you have a set of people who don’t speak foreign languages,” said Gordin, “They’re comfortable in English, they read English, they can get by in English because the most exciting stuff in their mind is happening in English. So you end up with a very American-centric, and therefore very English-centric community of science after World War II.”