Leonardo da Vinci and ADHD: Interest-gated attention, weaponized hyperfocus, and the two modes of noncompletion

This article advances a testable historical explanatory hypothesis: Leonardo da Vinci's (1452-1519) patterned noncompletion can be comparatively well explained by an ADHD-informed model of interest-gated attention and hyperfocus. A source-audited catalogue distinguishes two opposite outcomes: cold abandonment under weak enforcement, and prolonged retention and reworking-above all, in the Mona Lisa and the Virgin and Child with St Anne-alongside independent evidence of continuing technical or perceptual problems. The model predicts that active enforcement can support substantial delivery, weak obligation alone often cannot, and unresolved intrinsic problems can produce retention rather than release. A preliminary Michelangelo comparison tests whether the component outcomes are uniquely Leonardian and shows why terminal retention alone cannot carry the explanation. The claim concerns the organization of documented behavior rather than a retrospective clinical diagnosis. The resulting two-mode framework organizes otherwise contradictory evidence-cold abandonment alongside extraordinary sustained absorption-and defines a direct next test through blinded recoding and a larger comparison corpus.