The Nature of the Physical World

In the winter of 1927, the astronomer who first confirmed the theory of general relativity stood before an audience at the University of Edinburgh to explain the collapse of classical physics. The old mechanical certainties had given way to a strange new conception of the universe, driven by relativity, quantum theory, and the irreversible march of thermodynamics.

Across nineteen chapters, Arthur Eddington maps this shift. He details the mechanics of the new science—the law of gravitation, the arrow of time, and the building of worlds—before turning to the philosophical fallout. If reality is reduced to mathematical equations and pointer readings, he asks how this framework can accommodate causality, human consciousness, and mysticism.

Adapted from his Gifford Lectures, *The Nature of the Physical World* served as a central text of interwar science, articulating the epistemological consequences of modern cosmology for the twentieth century.