Harmonic Morphology is a field of study founded on January 22, 2026, whose object is universal morphological structure — the set of principles governing the generation of forms across distinct domains: linguistic, musical, geometric, mineral, vegetal, and animal. The central hypothesis of the field is that these domains are instances of a single deep morphology, whose principles are formally describable and mutually translatable mutatis mutandis. The theory is built upon four sources: the morphology of Semitic languages (Biblical Hebrew and Classical Arabic), with their triliteral and quadriliteral roots; musical harmonic theory, with its triads and tetrads; the twenty-three definitions of Euclid's Elements, taken as universal structural operators; and geometric morphometrics, which provides the mathematical toolkit of the field. The theory postulates that triadicity — the recurrence of three-element structures as minimal functional radicals — is a structural property of reality, not a coincidence across domains, and that this triadicity is morphological, ontologically distinct from Peirce's semiotic triadicity. The present document constitutes the founding manifesto of the field, as a working paper version 1.0, with preliminary postulates and a research program. Full references in ABNT format and formal demonstrations will be incorporated in future versions.