Before the quantum theory appeared, the principle of the uniformity of nature - that like causes produce like effects - had been accepted as a universal and indisputable fact of science. As soon as the atomicity of radiation became established, this principle had to be discarded.

Summary

This quote highlights the shift in scientific understanding brought about by the introduction of the quantum theory. Prior to its emergence, the principle of the uniformity of nature, which stated that similar causes result in similar effects, was widely accepted. However, with the discovery of the atomic nature of radiation, this principle had to be discarded. The atomicity of radiation challenged the idea of a deterministic and predictable universe, emphasizing the need to revise our understanding of cause and effect in light of quantum phenomena.

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