In the spirit of the child hero of The Emperor’s New Clothes, Ernst Mach (1838–1916) cleansed the intellectual atmosphere by making simple observations, obvious in retrospect, that unsettled conventional wisdom. Mach’s close critical analysis of the empirical value of physical concepts and his insistence that they must justify their use helped produce the atmosphere in which special and general relativity, and later quantum theory, could be conceived.
Mach’s masterpiece is The Science of Mechanics. 1 It is fascinating to read, even today, and every physicist ought to have that pleasure. In an annotated narrative, Mach dissects the conceptual innovations and presuppositions that marked the history of the science of motion, from its prescientific roots through the late 19th century. He was especially critical of Newton’s concepts of absolute time and space:
Here’s what Albert Einstein, in his self-styled “obituary,” said about Mach’s book:
Special relativity puts all spacetime...
