I was flipping through the paper and noticed an opinion piece by linguist and science writer Rik Smits, “Lefties aren’t special after all”:
Few truly insignificant traits receive as much attention as left-handedness. In just the last couple of generations, an orientation once associated with menace has become associated with leadership, creativity, even athletic prowess. Presidents Gerald R. Ford, George Bush, Bill Clinton and Barack Obama were born left-handed (as was Ronald Reagan, though he learned to write with his right hand). Folklore has it that southpaws are unusually common in art and architecture schools. Left-handed athletes like Tim Tebow and Randy Johnson are celebrated.
Sounds interesting so far. Then we get several paragraphs of history of how people got things wrong (authoritarians of past generations who forced lefties to use their right hands, silly “blank slate” ideologues, etc.).
What about the science? Smits writes:
Left-handers have been redefined as creative, broad-minded, natural leaders. Meanwhile, other studies continue to identify all sorts of negative associations with left-handers — clumsiness, propensity to die prematurely, higher breast cancer rates and greater vulnerability to suicide.
After reviewing hundreds of such studies for a book on left-handers, I [Smits] found that the evidence of positive qualities associated with left-handedness was anecdotal at best, while the scores of studies associating left-handedness with all manner of afflictions were generally too unreliable to have any practical consequence.
I’d have to see Smits’s book to judge (and, before you get on my case for commenting on a book that I haven’t read, please reflect that Smits chose to publish his article in the Times, and I think it’s expected that many people will write a newspaper article without reading the corresponding book. Certainly, when I wrote op-eds about Red State Blue State, I wanted these to stand on their own for the benefit of the vast majority of newspaper readers who were not reading the book), but I’m skeptical of his skepticism. The studies I’ve seen of handedness do have potential problems, so I wouldn’t object to labeling as “speculative” such claims such as “mathematicians are more likely to be left-handed” or “left-handers live shorter lives than right-handers.” At the same time, such claims are not scientifically implausible, and they do seem supported to some extent by the data.
I have not looked at the research on handedness recently, so I’m not sure whether Smits’s skepticism reflects new information or whether it is just a statement that the claimed findings about left-handers have not been proved. If the latter, I think it would be better to say that it’s not clear to what extent left-handers are different from the majority, rather than to say with such certainty that “lefties aren’t special at all.”
P.S. I’m right-handed. I don’t have any personal stake in all this; it’s a topic I got interested in awhile ago when Seth and I taught our class on left-handedness. At the time we recognized the weakness of the studies on the topic, but we also recognized weaknesses in sweeping arguments that attempted to dismiss the findings by arguing for selection effects etc. My impression at the time was that there was some evidence of interesting and important systematic differences between lefties and righties, but that it was also possible we were seeing nothing more than a bunch of statistical artifacts. My conclusion was that skepticism was warranted but it would be going too far to be certain that nothing was going on.