This appeared in the Pioneer in 1999
Laterality is the word used to describe the "specialized functioning in each hemisphere of the brain or in the side of the body which each controls" (Britannica). The most familiar example of this is called "handedness", the way that most of us favour the use of one hand over the other. But there is "handedness" in the way we use our eyes and our feet too.
You can check which of your two eyes is dominant by a simple test. Hold the forefinger of one hand about six inches away from your face, parallel with your nose. With both eyes open, centre the finger on some distant object like a vase or a lamp across the room from you. Close first one eye then the other. You will find that one of the eyes will reveal a view of the finger correctly centred on the vase or lamp while the other eye will show the finger displaced to one side. The eye with which you see the finger correctly centred is considered the dominant one. It does not necessarily follow that the side on which your hand is dominant will be the same one on which your eye is dominant.
According to the encyclopaedia, about three-quarters of right-handed and one third of left-handed people are right-eye dominant. Though the great majority of people are right-handed, there is no evidence to show that one side or the other is in any sense "better". Some famous lefties are: Napoleon, Einstein, Oprah Winfrey and Bill Gates.
I used to want to train my left hand for writing with so that I would have back-up in case I lost the use of my right hand. But it was a strain. Even now, I find that though I can form letters and if I concentrate hard, draw a simple object, it's not comfortable. My right hand rests nearby, "watching" as its companion does the thing that it does so much better. I can actually feel my right hand's tension and disapproval! It's as if the two hands have come to an understanding that this one will do a certain kind of work and the other one, the left one, well ... it accepts its place as the junior in this unique partnership they have, as the manual extremities of my body.
Of course, when both hands are engaged in using a key board, they are equally responsible. Sometimes I wonder if my left-hand feels happy about that or whether it would prefer to live a more indolent life. There was a time when I wanted to learn the guitar. To play it I needed to use my left hand to press down the strings of the guitar to form chords. One of the reasons I didn't progress very far was that I found it too difficult to think with my left hand. I could practically hear it, whining and complaining that this job of remembering chord arrangements and pressing down on the sharp steel strings was too much for it. It didn't mind the piano, however and for a while, both hands played happily together. But then I moved out of the house in which there was a piano and my musical education braked to a halt.
It is not clear to scientists what the purpose, if any, of laterality is. Why should there be a bias in favour of any one side? Why isn't everyone ambidextrous? Why aren't there as many lefties as righties? So far, there are no obvious answers. Some scientists believe that any child can be trained to prefer to use one particular hand. In recent years, however, there has been a movement away from interfering with a child's spontaneous preferences. I have certainly noticed that I meet more lefties nowadays, in India, than I used to. I believe this is because parents are no longer preventing their children from favouring their left hands, which used to be a traditional taboo.
Handedness interests me. It is a difference with which people are born, something they do not choose. The problems of adjustment they have in a world in which all kinds of ordinary implements are created for righties, from scissors to knives to the fixed writing tablets on academic-hall chairs to spiral binders, are the result of belonging to a minority. Though we are constantly pressurized to succumb to the demands of majority groups, here is an example of a naturally occurring group of people, which is completely normal but different.
Lefties gain some advantages by being different -- in sports or in battle, for instance, a lefty can sometimes win because righties are too used to being amongst other righties. The fact that there are lefties thriving amidst overwhelming numbers of righties is a reminder that being different does not mean being wrong. Lefties represent nature's celebration of variety. They are a challenge to the forces of vicious conformity that cause so much of the world's torment and bloodshed today.