Slippery reasoning that produces horrible results is unfortunately a regular occurrence in human history. While the 17th century witnessed the Scientific Revolution in Europe, sloppy logic (mixed with lack of information) led to some gruesome human experimentation. William Harvey had recently discovered (for Europeans) that blood circulates in our bodies, pumped by the heart, but there were centuries to come before scientists sorted out the function and composition of blood. A particularly incorrect – but common – notion that came into play in England in 1667 involved an educated but misfit-of-a-man named Arthur Coga. Arthur, and many others, thought that one’s blood conferred one’s personality, and that getting the blood of another could bequeath the characteristics of the donor into oneself. And so Arthur was paid a small amount as a volunteer to be among the first recipients of a blood transfusion. The donor? A sheep. The 17th-century diarist Samuel Pepys recorded Arthur’s own rationale for allowing this procedure: “The blood of a sheep has a symbolic power with the blood of Christ, because Christ is the lamb of God.” As far as we know, Arthur did not become a new messiah. However, he did survive the transfusion, which seems miraculous, since his body would have experienced the animal’s blood as pathogenic. Probably he had too small of an amount for his body to have rejected the blood.
Source(s): Samuel Pepys diary available online, entry from a footnote of Arthur Coga, edition by Henry Wheatly 1893. The Latin of Pepys’ recording of Coga reads “Sanguis ovis symbolicam quandam facultatem habet cum sanguine Christe, quia Christus est agnus dei.” Woodcut from 1491, Analdus de Villanova, ortus sanitatus, Wellcome Library.
