Z. Hadj-Allal, A. Makitie, A. Aarnisalo
For 140 years, hearing science and otology have rested on a premise treated as a principle of human physiology: that the sense of hearing, in health and disease, comes in distinct kinds. Its standard measure, the audiogram, was collapsed into a severity average and a subjective shape label. The reduction carried the premise from otology's founding fathers into the digital and artificial intelligence era. We tested this premise and falsified it. Human hearing does not resolve into a reproducible catalogue of types; it occupies a continuous, five-dimensional coordinate system. We call it the Human Hearing Atlas. Established across more than 4.29 million audiograms spanning 33 datasets, eight countries, 62 years and two calibration standards, the Atlas reconstructs unseen audiograms to near-decibel accuracy and preserves its clinical details. It maps within-ear hearing change over hours or decades, half of which is invisible to the conventional severity average. We demonstrate that the varying numbers of hearing types reported since 1932 are artifacts of 5 dB quantisation and cohort pooling. Finally, we establish the Law of Human Hearing States, characterized by four empirical invariants. The Atlas replaces arbitrary audiogram categories with positions and trajectories universal across individuals, populations and eras, opening a new paradigm for precision otology, genetics, epidemiology, regenerative medicine and clinical trials.