In 1849, the grammarian William Hall coined three new gender-neutral pronouns, ne, nis, and nim, deriving them from the Latin nonnemo, ‘someone, anyone.’ Hall introduced his new pronouns in the Encyclopedia of English Grammar, designed for the use of schools, academies, and private learners.
Hall explained that his new pronouns would fill a gap in the set of English personal pronouns, greatly benefiting users of the language: the pronoun he refers to masculine nouns like boy; she is used for feminines like girl; and it refers to “things without sex, as Wisconsin” (it's not clear why Hall referred to Wisconsin as "the sexless state"; all we know about him is that he published his grammar in that part of Virginia that would later become West Virginia.)
Hall reminded readers that English lacks a pronoun to use for nouns like animals and parents, which refer to both genders. These are nouns of the “common gender.” There's also no pronoun for “one of either sex, as parent, bird, without defining which sex it belongs to.” Hall called this fifth gender category the “either gender.” That's where ne, nis, and nim come in. They are singular pronouns for use with singular nouns that can refer to either sex but that don’t specify that sex.
Without ne, nis, and nim, speakers and writers must choose one of three unsatisfactory options: generic he, the phrase he or she, or using the plural pronoun they as a singular. Each of these options has major drawbacks. The generic masculine he is often ambiguous: sometimes he includes women and sometimes it means “only men.” Insisting on he can also produce the kind of absurd sentence in the second panel of the Peanuts cartoon below, where Lucy must refer to herself as he:
In this Peanuts comic, we see the absurdity of generic “he.” Charles M. Schulz, July 24, 1970.
So much, then, for the generic he. The next option, using the coordinate he or she, was universally condemned as wordy, repetitive, and awkward. And in his day, singular they was typically ruled ungrammatical. Hall believed that only a new set of common gender singular pronouns, ne, nis, and nim, could eliminate such problems. Plus if readers didn't like ne, nis, and nim, they were free to propose a different set. Many writers did just that.
Hall wasn't the only grammarian to recognized the pronoun gap. From the late eighteenth century on, a number of writers had noted that English lacked a third-person, singular, gender neutral pronoun, one that referred to either sex, or to both sexes. Occasionally someone would suggest re-purposing an existing word to fill the gap, words like it or that. Or they'd borrow something from another language, like le or un, from French. Or, like Hall, they'd coin a new pronoun.
Until recently, these pronoun coiners assumed that sex was binary. But in the 1790s, the Scottish philosopher James Anderson proposed thirteen different grammatical genders to account for the complex sexual variation that he found among both animals and humans. Fortunately for us, Anderson did not create thirteen new pronoun sets to go with all those genders.
The earliest gender-neutral English pronoun proposal that I've managed to find appeared a few years before Hall created ne, nis, and nim. The physician and part-time grammarian Francis Augustus Brewster coined E, es, and em in 1841. We would call such pronouns gender neutral, but Brewster called them “masculor feminine,” from the Latin medical term masculofemina. That literally means ‘man-woman,’ and was a term describing people born both male and female (the term hermaphrodite, a Greek derivation combining Hermes and Aphrodite, was also used in the medical literature). As a doctor, Brewster would be familiar with the terms, and his use of masculor feminine for his new pronoun set suggests that E, es, and em may actually be the first nonbinary pronouns, if not the first trans pronouns. Unfortunately for us, Brewster just labeled his coinage without explaining his intention.
Brewster was able to take enough time from his clinical practice to write a grammar. The only surviving copy is in the Yale University library, perhaps because Brewster sent it to his alma mater.
Today, pronouns like E, es, em and ne, nis, nim are often called neopronouns. "Neo" means new, but these pronouns, some of them coined 185 years ago, aren’t new at all. Charles Crozat Converse, a prominent American attorney and composer who wrote hymns that are still popular, coined the common gender pronoun thon in 1858. Many other writers, both professional and amateur, also thought they could supply the missing pronoun—and many newspaper accounts of their coinages were headed either “Wanted: A New Pronoun” or “The Missing Word.”
This call for a new pronoun to replace the “illiterate” use of singular they or the “more absurd” generic he appeared in 1878.
The “missing word” was in the news in 1868, when a report in the New York Times credits ne, nis, and nim to a “Dr. Butler” (without specifying which Dr. Butler), though it’s now clear that the paradigm was coined twenty years earlier by William Hall. Pronoun discussions continued into 1879 when, responding to a discussion of common gender pronoun proposals in the Atlantic, the editors of The Ohio Educational Monthly, the magazine of the Ohio Teachers Association, condemned ne, nis, and nim along with the upstart pronouns e, es, em; hesh, hizer, himer; che, chers, cher, and all other “missing word” proposals. Instead of a new word, the Ohio teachers recommended that grammarians accept what “the people” had already accepted, singular they: “Let us hear no more of a new pronoun, but let our bold writers and speakers add their influence in adding a new use to an old pronoun.”
Despite this early endorsement from teachers, singular they continued to be shunned, and so pronoun coiners continued to ply their trade. Between the 1860s and 1950, 200 or more new pronoun sets appeared. Two such pronouns, thon and heer, were successful enough to make it into dictionaries, but English speakers didn't start using gender-inclusive pronouns in significant numbers until recently. The past couple of decades have seen more and more people adopting nonbinary pronouns like ze (first coined in 1864!), se (1874), heer (1911) and hir (1920), along with many, many others. So popular are these gender-inclusive pronouns that a number of conservative-led states have tried to ban their use, and a conservative justice of the U.S. Supreme Court even spent seventy pages of a dissenting opinion arguing that forcing someone to use gender-inclusive pronouns is unconstitutional.
Along with the increased use of neopronouns, singular they has finally been rehabilitated. It took a little over a century, but the Ohio teachers’ wish has now become a reality. Singular they has been a feature of the English language—not a bug—since 1375, and it's now the one nonbinary pronoun almost universally approved by English grammars, dictionaries, and usage guides.
Singular they is popular with people who are trans or nonbinary. But it's also commonly used by people who insist that gender is always binary, people who want everyone to show their birth certificates before using a public restroom. English majors use singular they when they're not taking a test. Even English teachers use it when they're not in class. Some of them have even been known to tell their students that singular they is perfectly acceptable.
You'll also find singular they in the speech and writing of those who believe that grammar rules were set in stone back in biblical days, thousands of years before anyone even spoke English. Ask them point blank and they'll insist that singular they is illiterate and ungrammatical, but even they use it all the time when they're not paying attention.
So here's my advice, not that you asked for it: Use whatever pronoun you want, and if anybody objects, just tell them, "Hey, it's a free country. You can't tell me what to do."
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You can find more about the history of gender pronouns old and new in my book, What’s Your Pronoun? Beyond he and she (Liveright, 2020), available wherever you buy or borrow books. H/t to Elliot Jude Vanderstroom for finding Hall’s 1849 coinage of ne, nis, and nim, and the 1879 editorial favoring singular they in the Ohio Educational Journal.