While sitting in the Oval Office with NATO Secretary General Mark Rutte on Friday, US President Donald Trump was asked what he thought of leaders from Russia, Iran and China meeting to discuss ...

The good sheik evidently holds the Copernican theory to be a "mere theory," not a "fact." In this he is technically correct. A theory can be verified by a mass of facts, but it becomes a proven ...

This article was originally published with the title “ The Origins of the Copernican Revolution ” in Scientific American Magazine Vol. 215 No. 4 (October 1966), p. 88 doi:10.1038 ...