Is Science Mostly Driven by Ideas or by Tools?

The physical sciences have alternated between revolutions driven by new ideas and explorations driven by new tools. Thomas Kuhn was a theoretical physicist before he became a historian. He saw the history of science through the eyes of a theorist. He gave us an accurate view of events in the world of ideas. His favorite word, “paradigm,” means a system of ideas that dominate the science of a particular place and time. A scientific revolution is a discontinuous shift from one paradigm to another. The shift happens suddenly because new ideas explode with a barrage of new insights and new questions that push old ideas into oblivion. I remember the joy of reading Kuhn's book, The Structure of Scientific Revolutions, when it first appeared in 1962. It made sense of the relativity and quantum revolutions that had happened just before the theoretical physicists of my generation were born. Those were revolutions led by deep thinkers—Einstein and Heisenberg and Schrödinger and Dirac—who guessed nature's secrets by dreaming dreams of mathematical beauty. Their new paradigms were created out of abstract ideas. In those revolutionary years from 1900 to 1930, ideas led the way to understanding.