Who is credited with the discovery of circulation?

William Harvey is credited with the discovery of blood circulation, a groundbreaking development in the understanding of the human cardiovascular system. In the early 17th century, he published his findings in the work "De Motu Cordis" in 1628. Harvey's meticulous experiments and observations led him to demonstrate that the heart functions as a pump, circulating blood throughout the body in a closed system. This was a significant departure from previous beliefs that blood was produced in the liver and consumed by the body. His work laid the foundation for modern physiology and greatly advanced the study of medicine by establishing the principles of circulation.

The other figures mentioned, while significant in their own rights, contributed to different areas in medicine or anatomy. John Hunter was known for his work in surgery and anatomy, Joseph Crandall focused on public health and sanitation, and Edwin Chadwick was known for his work on social reform and public health, notably in sanitation and urban health conditions. None of these individuals made the same pivotal contributions to the understanding of blood circulation as Harvey did.