Whether caused by genetics or chance, at this stage our handedness, and the causes for and consequences of, have no definitive scientific explanations. What researchers do know is that lefties make up between 5% to 15% of the world’s population and that men are more likely to be left-handed than women.
The word left derives from the Anglo-Saxon lyft, meaning broken, weak, or defective. The French word for left, gauche, also means clumsy. The word sinister, meaning evil, suspicious, under-handed and dangerous, derives from Latin sinistra, which means left. Sinistral is a word used to describe left-handedness.
The devil himself is believed to be left-handed. In the tarot, he holds a burning torch in his left hand. In medieval times, being left-handed was associated with being possessed by the devil and was severely stigmatized. This residual superstitious belief played out until even in recent history in the lives of lefties who as kids were punitively forced to write with their right hands.
Being left-handed may signal a strong right brain in the person, meaning they might be gifted with language skills and creativity. Whereas the brains of right-handed people might be asymmetrical, with left cerebral hemispheres being larger than the right, apparently lefties more often have symmetrical brains and may be quicker thinkers, who use both sides of their brain more efficiently. Lefties have a cognitive advantage for video games, mathematics and architecture, and are better at divergent thinking and problem solving.
Lefties are advantaged in interactive sports, such as boxing, fencing, tennis and baseball. 25% of big league baseball players are lefties and up to 40% of the best tennis players are lefties. Lefties also seem to have a better chance of having a high IQ. Apparently, as many as 20% of Mensa members are left-handed.
In the USA, 4 out of 7 presidents have been left-handed: James A. Garfield, Herbert Hoover, Harry S. Truman, Gerald Ford, Ronald Reagan, George H.W. Bush, Bill Clinton and Barack Obama. Other famous left-handed geniuses include Charles Darwin, Albert Einstein, Benjamin Franklin, Isaac Newton, Steve Jobs and Bill Gates.
Lefties might have a higher prevalence for behavioral problems, dyslexia, psychotic illnesses schizoaffective disorder and alcoholism. They are more susceptible to insomnia, allergies and asthma than right-handed people, but may have a lower rate of arthritis and ulcers.
And finally, August 13 is International Left-Handers Day, where the lefties in the world unite in their experiences of the challenges of living in a right-handed world.