This sentence was said by French microbiologist and chemist Pasteur. The original words are "Although science has no national boundaries, scholars have their own countries". The Curies have a famous saying that "science knows no borders". After Germany occupied France, the Frenchman Pasteur returned the honorary certificate given to him by his alma mater, Bonn University. When people advised him that "science has no borders", he added the following sentence after "science has no borders": "But scientists have their motherland". It was really a shock.