"The violent reaction on the recent development of modern physics can only be understood when one realises that here the foundations of physics have started moving; and that this motion has caused the feeling that the ground would be cut from science"

In this quote, Werner Heisenberg is talking about the extreme and typically unfavorable reaction to the improvements in modern physics. He argues that this response can just be comprehended if one acknowledges that the very core of physics is being challenged and changed. The foundations of physics, which have actually long been considered steady and constant, are now in motion. This has actually triggered a sense of anxiousness and unpredictability, as it seems like the very ground on which science stands is being taken away. Heisenberg suggests that this is the reason for the violent response, as people have a hard time to come to terms with the moving and evolving nature of physics.