At the same time, however, German doctors viewed blood transfusion as an "omen of danger," fearing it would defile pure blood, even though the life-saving procedure had been successfully used in British and American hospitals since the end of World War I.
For most doctors, mixing the blood of a German with that of a Jewish citizen was also unthinkable. Transfusions between men and women were also suspect, out of concerns that the blood might impart female characteristics to a male recipient.
Using Blood to Judge Superiority and Character
It was the Hirszfelds who laid the foundation for this fanaticism with their blood group study. When the British Medical Journal initially rejected the study, Ludwik Hirszfeld found solace in the knowledge that the significance of Einstein's theory of relativity had also been initially underestimated. Eventually, the British medical journal The Lancet published the Hirszfelds' adventurous findings from the soldiers' camp.
Hirszfeld and other blood researchers of the era considered it self-evident that the various blood groups were indications of inferior or superior racial characteristics. These scientists were also convinced that personality traits could be inferred from the blood.
To explain the existence of the various blood groups, Ludwik Hirszfeld developed a theory that today seems altogether absurd. He believed that, in some distant past, there had been just two "primordial races" -- carriers of blood group A, who originally lived in the west and north, and carriers of blood group B, native to the south and east. The gradual mixing of these two peoples over the millennia, he speculated, created the other blood groups.
Liberally minded academics and racist agitators alike saw this mixing as wrong. This puts Jewish researchers among those who paved the way for the extreme anti-Semitism that followed. Spörri finds that this fact "doesn't require any further explanation beyond the fact that these scientists of Jewish ancestry saw themselves first and foremost not as Jews, but as scientists."
The researchers unanimously agreed that possessing type B blood was a sign of degeneracy. Bacteriologist Max Gundel believed he had observed more "individuals identified as inferior" among carriers of type B blood, and that the blood group was especially common among "psychopaths, hysterics and alcoholics, as is the case with brunette individuals as well."
Mistaken Beliefs about a Persistent Mystery
The true origin of blood groups remains a mystery to this day. What can be said for certain is that type O occurs more frequently in the Americas and Africa, while type B is more common in Asia and type A in Europe.
Today's researchers see the key to understanding blood groups in the particular characteristics possessed by each group. People with type O blood, for example, possess greater immunity to malaria. Scientists thus believe that this blood group developed in Africa millions of years ago as an evolutionary response resulting from a mutation of type A blood. Type B blood, meanwhile, possesses a higher degree of immunity to the plague and may have developed in areas where that illness was especially devastating. Blood groups, however, have nothing at all to do with personality traits.