Those to whom intellectual freedom is personally important may be a minority in the community, but among them are the men of most importance to the future. We have seen the importance of Copernicus, Galileo, and Darwin in the history of mankind, and it is not to be supposed that the future will produce no more such men. If they are prevented from doing their work and having their due effect, the human race will stagnate, and a new Dark Age will succeed, as the earlier Dark Age succeeded the brilliant period of antiquity.
Source: Religion and Science, 1935, chapt. 10: Conclusion
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