William Harvey

Revolutionized medicine by discovering the circulatory system and the heart's role in blood movement

William Harvey (1578–1657) was an English physician whose groundbreaking work De Motu Cordis (1628) fundamentally altered the understanding of human physiology. Before Harvey, medical knowledge relied heavily on Galen's theories, which inaccurately claimed that blood was produced in the liver and consumed by organs. Harvey's meticulous experiments and observations proved that blood circulates continuously through the heart and vessels, driven by the heart's contractions.

Harvey's discovery was met with skepticism, as it contradicted centuries of accepted dogma. He used quantitative methods, calculating that the heart pumps far more blood than the body could possibly produce daily, laying the foundation for evidence-based medicine. His work not only corrected anatomical misconceptions but also inspired future scientists like Marcello Malpighi, who later discovered capillaries, completing Harvey's circulatory model.

Beyond physiology, Harvey's emphasis on empirical research challenged the authority of ancient texts, accelerating the Scientific Revolution. His legacy persists in modern cardiology, and his methods remain a cornerstone of scientific inquiry.