The Canadian author Lawrence Hill has had “a lifelong obsession” with blood, because of his mixed-race parentage. His fascinating study considers all of its aspects – scientific, cultural, psychological, political – and explores its contradictions: healing and disease, guilt and innocence, elevation (“blue blood”) and denigration (the “one-drop rule” that imposed inferior status on those of African ancestry in the US). Harvey showed the basics of circulation in 1628 (using a live dog), but it wasn’t until the discovery of blood types, in the early 20th century, that safe transfusions were possible, and the world wars led to huge advances. Yet there followed the perception that blood signified race: in the US, blood from black donors could not be given to whites. Hill had viewed his own blood with ambivalence until a life-saving transfusion convinced him that blood is no measure of racial identity.
