In the late 19th century, many physicists thought that their job was almost finished, for well-understood mathematical laws could explain most of the observed physical phenomena. There were only a few things lacking explanation, but physicists thought that they were just details. They believed that soon it would be possible to describe the behavior of any system. (There is the story of a student who asked Lord Kelvin what he would advise him to choose to research in Physics, and Kelvin replied that he should choose another area, for Physics was almost “complete”.)
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Sophia of Nature 