Ernst Mach 1838 – 1916

Ernst Mach was an Austrian physicist and philosopher of science whose work helped to inaugurate twentieth-century philosophy of science. His Mechanics in Its Development subjected the foundations of Newtonian physics to a thoroughgoing empiricist critique, while The Analysis of Sensations argued that the basic elements of all scientific description are sensations, and that physics should be the economic ordering of these. His phenomenalism deeply influenced the early Vienna Circle and the early Einstein, even as the latter eventually moved beyond it. The Mach number in fluid dynamics is named for him.

Ernst Mach was born in 1838 at Chrlice, then in Moravia, the son of an estate manager and lay tutor. He took his doctorate at Vienna in 1860, taught at Graz, and held the chair of experimental physics at Charles University in Prague from 1867 to 1895; he then occupied the chair specifically created for him at Vienna in the philosophy of the inductive sciences until a stroke ended his teaching in 1901. He was elevated to the Austrian House of Lords in 1901.

His scientific output included pioneering work on the physiology of perception, on the propagation of shock waves around supersonic projectiles (whence the Mach number), and on the historical-critical analysis of mechanics. His major books include The Science of Mechanics (1883), The Analysis of Sensations (1886), Knowledge and Error (1905), and Popular Scientific Lectures.

Mach argued that scientific concepts should be the economical organization of relations among sensations, criticized Newton's absolute space and time on what came to be called Machian principles, and refused on positivist grounds the physical reality of atoms even after most of his colleagues had accepted them. His epistemological writings shaped Einstein's thinking about general relativity, the Vienna Circle, and the early Soviet Marxists. He died at Vaterstetten in Bavaria in February 1916.