British English, American English, Noah Webster English, or New Yorker English? Let's just pick one and stick with it.
Can we all agree that the color is grey, not gray? Or gray. That, too, would be totally fine. Each variation has a weighty pedigree, and it wasn't until the 19th century that the current pattern--what's gray in the United States is grey across the sea--emerged. As late as 1893, The Times of London had a preference for grayness, as did the great Samuel Johnson (his 1755 opus, A Dictionary of the English Language, was taken as the definitive compendium of the English language until the arrival of the Oxford version--and let's remember that Dr. Johnson was British). The esteemed London printing houses of William Clowes and Sons and Eyre & Spottiswoode (the King's Printer), on the other hand, stood by a greyer usage. But even then, opinions on either side of the argument were too deeply entrenched for change--so much so that people went as far as to argue that the two words had different meanings altogether: Grey "a more delicate or a lighter tint than gray," and gray the "'warmer' colour." The last century has done little to quell the disagreement; if anything, each side of the ocean now has its very own linguistic army.
But isn't it time to lay down the sword? Or is English to remain a language whose spelling varies from country to country, publication to publication--and even within the same publication if you happen to catch it at different times or different editorial reigns? Gray or grey is the least of the problem. Over the last 200 or so years, strange discrepancies have cropped up wherever you look.
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Many now-common differences can be traced to Noah Webster's proposed reforms in the late 1700s and early 1800s, after America had gained its independence from Britain. Why did the language need to be reformed, one might (reasonably enough) ask? Not, it seems, because it was suffering from any particular malady, but because it would be a way to assert American independence, not just of land but of mind and spirit. "The alteration, however small," wrote Webster in his 1789 "Essay on the Necessity, Advantages, and Practicality of Reforming the Mode of Spelling and of Rendering the Orthography of Words Correspondent to Pronunciation"--his take on the topic over a decade before his first eponymous dictionary, with its mellower rhetoric, was released--"would encourage the publication of books in our own country. It would render it, in some measure, necessary that all books should be printed in America. The English would never copy our orthography for their own use." So was the goal of the changes to improve efficiency (a point he would later argue)--or to spite the English?