Our eloquent hands
Physicians reject palmistry as nonsense. But reading the creases of our palms for hidden meaning is what doctors have always done- by Alison BashfordRead on Aeon.
The article explores the historical connection between palmistry—the practice of reading palms for character or future predictions—and medicine. Palmistry, often dismissed as occult or pseudoscience today, was once a respected medical tool. For example, the simian line (a single crease across the palm) was used in diagnosing Down’s syndrome (trisomy 21) until the 1950s. This line appears in up to 5% of humans and is also found in some primates, like gorillas. Historian of medicine Charlotte Wolff studied palm prints of both humans and animals in the 1930s, including a gorilla named Mok, highlighting how palmistry blurred the lines between medicine and mysticism.
Several influential figures linked palmistry to medicine. In 1663, Isaac Newton bought a palmistry book, Palmistry, the Secrets Thereof Disclosed, which treated palm reading as a mathematical science. In the 1920s, physician Francis Crookshank claimed the Virgin Mary had a simian line, illustrating how palmistry was integrated into medical and religious discourse. Later, geneticist Lionel Penrose (1930s–1950s) used palm prints statistically to study genetic traits, including Down’s syndrome. Even after the genetic cause of trisomy 21 was discovered in 1959, researchers like Jérôme Lejeune continued exchanging palm-print diagrams, showing the lasting medical relevance of palmistry.
Palmistry’s legacy persists in modern medicine. Midwives still check neonatal palms for the simian line because it correlates with Down’s syndrome, though not exclusively. In the 1960s, a related crease called the Sydney line was identified, and as late as 1990, prenatal ultrasounds were used to detect the simian line in fetuses. Today, some hospitals inform parents that a simian crease may be observed during newborn exams. This practice reflects medicine’s broader reliance on interpreting bodily signs—rashes, nail color, or palm patterns—to diagnose conditions, a tradition rooted in historical palmistry.
The human hand’s anatomy has been studied both scientifically and mystically. In 1833, anatomist Charles Bell wrote The Hand, describing the hand’s design as evidence of God’s purpose. Charles Darwin later linked the hand’s evolution to human dominance, noting that upright posture freed the hand for tool use. In the 1820s, anatomist Jan Evangelista Purkinje analyzed palm creases but used traditional palmistry terms like life line or line of Venus. Even Darwin’s contemporary, Friedrich Engels, incorporated the hand into his theories of human history, emphasizing its role in labor and tool use.
The study of palm and finger patterns, called dermatoglyphics, bridges palmistry and genetics. Francis Galton, known as the father of fingerprinting, also explored palm prints in the late 19th century, wondering if palm lines were as unique as fingerprints. Lionel Penrose later used dermatoglyphics to correlate palm patterns with genetic conditions like Down’s syndrome. In 1959, researchers discovered that trisomy 21 (an extra chromosome) matched the simian line’s phenotype. This discovery validated palmistry’s long-standing observations, showing how visible traits can reveal hidden genetic information.
Medicine relies on *medical semiotics*—the interpretation of bodily signs to diagnose conditions. A *sign* is an observable trait (e.g., a rash or palm crease) that indicates a hidden condition (e.g., measles or Down’s syndrome). Physicians are trained to read these signs, much like palmists once did. Francis Crookshank, a 1920s physician, even argued for a *theory of signs* in medicine, blending linguistic and medical analysis. Today, the simian line remains a taught example of how physical traits can guide clinical decisions, demonstrating palmistry’s enduring, if indirect, influence on modern medicine.
