In the last post, I said that the debate over whether data is singular or plural is ultimately a question of how we know whether a word is singular or plural, or, more accurately, whether it is count or mass. To determine whether data is a count or a mass noun, we’ll need to answer a few questions. First—and this one may seem so obvious as to not need stating—does it have both singular and plural forms? Second, does it occur with cardinal numbers? Third, what kinds of grammatical agreement does it trigger?
Most attempts to settle the debate point to the etymology of the word, but this is an unreliable guide. Some words begin life as plurals but become reanalyzed as singulars or vice versa. For example, truce, bodice, and to some extent dice and pence were originally plural forms that have been made into singulars. As some of the posts I linked to last time pointed out, agenda was also a Latin plural, much like data, but it’s almost universally treated as a singular now, along with insignia, opera, and many others. On the flip side, cherries and peas were originally singular forms that were reanalyzed as plurals, giving rise to the new singular forms cherry and pea.
So obviously etymology alone cannot tell us what a word should mean or how it should work today, but then again, any attempt to say what a word ought mean ultimately rests on one logical fallacy or another, because you can’t logically derive an ought from an is. Nevertheless, if you want to determine how a word really works, you need to look at real usage. Present usage matters most, but historical usage can also shed light on such problems.
Unfortunately for the “data is plural” crowd, both present and historical usage are far more complicated than most people realize. The earliest citation in the OED for either data or datum is from 1630, but it’s just a one-word quote, “Data.” The next citation is from 1645 for the plural count noun “datas” (!), followed by the more familiar “data” in 1646. The singular mass noun appeared in 1702, and the singular count noun “datum” didn’t appear until 1737, roughly a century later. Of course, you always have to take such dates with a grain of salt, because any of them could be antedated, but it’s clear that even from the beginning, data’s grammatical number was in doubt. Some writers used it as a plural, some used it as a singular with the plural form “datas”, and apparently no one used its purported singular form “datum” for another hundred years.
It appears that historical English usage doesn’t help much in settling the matter, though it does make a few things clear. First, there has been considerable variation in the perceived number of data (mass, singular count, or plural count) for over 350 years. Second, the purported singular form, datum, was apparently absent from English for almost a hundred years and continues to be relatively rare today. In fact, in Mark Davies’ COCA, “data point” slightly outnumbers “datum”, and most of the occurrences of “datum” are not the traditional singular form of data but other specialized uses. This is the first strike against data as a plural; count nouns are supposed to have singular forms, though there are a handful of words known as pluralia tantum, which occur only in the plural. I’ll get to that later.
So data doesn’t really seem to have a singular form. At least you can still count data, right? Well, apparently not. Nearly all of the hits in COCA for “[mc*] data” (meaning a cardinal number followed by the word data) are for things like “two data sets” or “74 data points”. It seems that no one who uses data as a plural count noun ever bothers to count their data, or when they do, they revert to using “data” as a mass noun to modify a normal count noun like “points”. Strike two, and this is a big one. The Cambridge Grammar of the English Language gives use with cardinal numbers as the primary test of countability.
Data does better when it comes to grammatical agreement, though this is not as positive as it may seem. It’s easy enough to find constructions like as these few data show, but it’s just as easy to find constructions like there is very little data. And when the word fails the first two tests, the results here seem suspect. Aren’t people simply forcing the word data to behave like a plural count noun? As this wonderfully thorough post by Norman Gray points out (seriously, read the whole thing), “People who scrupulously write ‘data’ as a plural are frequently confused when it comes to more complicated sentences”, writing things like “What is HEP data? The data themselves…”. The urge to treat data as a singular mass noun—because that’s how it behaves—is so strong that it takes real effort to make it seem otherwise.
It seems that if data really is a plural noun, it’s a rather defective one. As I mentioned earlier, it’s possible that it’s some sort of plurale tantum, but even this conclusion is unsatisfying.
Many pluralia tantum in English are words that refer to things made of two halves, like scissors or tweezers, but there are others like news or clothes. You can’t talk about one new or one clothe (though clothes was originally the plural of cloth). You also usually can’t talk about numbers of such things without using an additional counting word or paraphrasing. Thus we have news items or articles of clothing.
Similarly, you can talk about data points or points of data, but at best this undermines the idea that data is an ordinary plural count noun. But language is full of exceptions, right? Maybe data is just especially exceptional. After all, as Robert Lane Green said in this post, “We have a strong urge to just have language behave, but regular readers of this column know that, as the original Johnson knew, it just won’t.”
I must disagree. The only thing that makes data exceptional is that people have gone to such great lengths to try to get it to act like a plural, but it just isn’t working. Its irregularity is entirely artificial, and there’s no purpose for it except a misguided loyalty to the word’s Latin roots. I say it’s time to stop the act and just let the word behave—as a mass noun.