I must first cop to my bias: I’m left-handed. All my life I’ve cursed spiral notebooks, struggled with right-handed ladles, squirmed uncomfortably in right-handed writing desks and bumped elbows with fellow diners.
I’m certainly not alone. Lefties make up about 10 percent of the population worldwide. Anthropological evidence indicates that ratio has been consistent over the past 300,000 years.
The scientific term for left-handed is sinistral chirality. But we’ve also been called caggy, clicky, skivvy-handed, ballock-handed, gibble-fisted and corrie-pawed.
The English language has been less than flattering toward us. The word left comes from the Anglo-Saxon lyft meaning weak or broken. My Webster’s New World Dictionary includes clumsy, awkward, insincere and dubious among its definitions for left-handed.
Many everyday phrases are equally insulting: A “left-handed compliment” is an insult. A “left-handed marriage” is an extramarital affair. A “left-handed wife” is a mistress.
Traditional religions are heavily biased toward right-handedness. Catholic priests symbolize the “strong right hand of God.” Medieval Jewish philosopher Maimonides (A.D. 1135-1204) listed being left-handed as a blemish for priests. In the Bible, the right hand is mentioned positively 100 times; the left hand is only mentioned 25 times — all negatively. In Scotland, an unlucky person is said to “have been baptized by a left-handed priest.”
It’s unclear what determines left-handedness. The role of inheritance is complex and poorly understood. For instance, if both parents of a child are left-handed, there is only a 26 percent chance that the offspring will be left-handed. But a twin study from the University of Nottingham — published Sept. 25, 2013, in the journal Heredity — found “no strong genetic determinant” for handedness.
Other theories include the age of the mother. Women who give birth over the age of 40 are 128 percent more likely to have left-handed babies than women in their 20s. Stanley Coren writes in “The Left-Hander Syndrome: The Causes and Consequences of Left-Handedness” that there is a connection between trauma during gestation or birth and left-handedness. There’s also evidence that exposure to testosterone in utero increases the chances and may account for the fact that men are more likely to be left-handed by 4 percentage points.
Whatever the cause, being left-handed has a big impact. Lefties are more likely to be intellectuals. Tests conducted by St. Lawrence University in New York found more people with an IQ over 140 were lefthanded than right-handed. They’re purported to be more creative and better at spatial awareness, math and architecture.
One-quarter of Apollo astronauts were southpaws. Three of the last four presidents were left-handed. Counting back as far as Harry S. Truman, the number is five out of 12. It’s also a huge advantage in sports that involve one-on-one contact, such as boxing, baseball and tennis.
But there’s a significant downside. Left-handed people have higher incidents of alcoholism, schizophrenia, dyslexia, Crohn’s disease, stuttering and autism. The Boston Strangler, Jack the Ripper and Osama Bin Laden were notorious lefties.
They also tend to have a shorter lifespan and may die as early as nine years earlier than right-handers. Thank goodness we’re now more enlightened and view left-handedness as a natural variation. And we’ve stopped slapping left-handed kids’ hands in school to make them use the other hand. Still, we have to recognize that lefties come with different wiring and accept all that it entails.