AN EXTRAORDINARY human superpower has long been hidden in plain sight, a secret weapon as easy to spot as the nose on your face…because it is the nose on your face. Contrary to popular belief, humans have an excellent sense of smell. And the story behind why we ever thought differently is an incredible illustration of how facts can be buried by bias.
In a newly published paper in Science, neuroscientist John McGann, who studies sensory perception at Rutgers University, explains how religious politics in 19th-century France spurred the misconception that humans have a poor sense of smell. The Catholic Church objected to what it deemed the teaching of atheism and materialism, particularly the courses taught at the University of Paris Medical School by an anatomist named Paul Broca whose work focused on the brain.
The criticism, writes McGann, worried Broca, who needed to find evidence to support his view that the mysteries of life could be reduced to simple scientific facts. For example, McGann explains that Broca, who subscribed to Charles Darwin’s theories about evolution, first published in 1859, did not think the human soul existed separately from the human body. Based on his observations that humans have larger frontal lobes—the portion of the brain behind our forehead—than other mammals and that damage to this region could impair speech and cognition, Broca concluded that this mass must be where the soul resided. That conclusion went against the beliefs embraced by strong and powerful religious leaders at the time, who held that the soul was created by God, was the seat of consciousness and freedom, was not confined to any single part of the body and did not die with the body.