FREDDIE DEBOER, a graduate student and blogger, has just summed up his class project examining the use of singular they. It will be hard going for most readers, using as it does terms like "anaphor" and "c-command" that aren't part of ordinary school and university grammar-teaching. After his technical analysis of the few cases where singular they is allowed (as in "every student aced their project"), he sums up for the lay reader:

Using "their" for singular antecedents is one that I think people need to just give up on. As I've argued, it only occurs in a very limited set of circumstances, and those circumstances [are very] unlikely to produce confusion about what is meant. We all know what is intended in such a statement, to the point that most of us don't even notice it in spoken conversation. And as we lack a satisfying alternative, the usage is likely to persist. That's not to say that you shouldn't understand what the "rule" is, if only to be able to satisfy those gatekeepers that police it. (Don't use it in your resume, don't use it in your grade school application.) But this is an example of a gate that's not worth defending anymore.

It's a nice piece of work, but it's useful to revisit the old question of singular they, and go deeper into two of Mr deBoer's arguments, one of which he makes explicitly, and one of which he waves away.

First, the argument he waves away:

When dealing with scolds, it's nice to be able to point out that "they" was used as a singular pronoun for centuries before anybody said that you couldn't. But we shouldn't be tempted to take that as dispositive when we are trying to avoid exactly that kind of rigidity.

He's right that no single argument is dispositive. Tradition alone must contend with the modern vox populi and with logic when we ask "what's correct?" But many who oppose singular they do so precisely on historical grounds. Such people argue that singular they is a product either of sloppy modern grammar teaching or of political correctness (that is, the desire to avoid "Every student aced his project").

If singular they has deep historical precedent, then it is dispositive on the sub-question of what is traditionally correct. In this case, liberal descriptivists and conservative prescriptivists can sing a happy song in harmony. Descriptivists note that nearly everyone uses singular they, at least in speech. Prescriptivists can relax in the knowledge that Chaucer, Shakespeare, the King James translators, Swift, Byron, Austen, Goldsmith, Thackeray, Shaw, Herbert Spencer and others used it. In collecting these examples, the "Merriam-Webster Dictionary of English Usage" notes that these are not "lapses" by the greats. They are the regular pattern, many centuries old. The "prohibition" of singular they is only two centuries old. This simply should not be a controversy.

What about the fear of confusion? We should avoid even technically correct usages if they are ambiguous. Mr deBoer says that singular they is "very unlikely to produce confusion". I'd go beyond "very unlikely". It's always possible to create a fake sentence in isolation that might be ambiguous. "Many professors make every student buy their own books." Hm, are the students forced to buy their own books (rather than being allowed to use library copies)? Or are the professors, in their vanity, requiring students to buy the books that the professors wrote?

This example, which took me a while to come up with, is genuinely ambiguous. But such statements, already rare, are never said in a vacuum, the entire utterance of a speaker who walks up to you, says it, and walks away. Instead, this will be appear in a context like "It's a shame that universities don't put multiple copies of required books in the library where poorer students can get at them for free. Many professors make every student buy their own books." Or "Professors shouldn't abuse their discretion to push their own academic theories or line their own pockets, but many professors make every student buy their own books." I think it is nearly literally impossible for singular they to be confusing in an actual conversation or in a longer piece of writing. Readers are invited to try to construct such an example to prove me wrong. And that still doesn't prove singular they ungrammatical. Richard told John he loved his wife is ambiguous, but grammatical. And as above, context (a bit of knowledge of Richard's and John's love lives) will almost certainly save the day.

What arguments are left? It's illogical? Yes, they is normally plural, and everyone takes a singular verb. But this is a case for saying, simply, "they is both singular and plural." After all, you is both singular and plural, after going down a long and winding etymological road. And singular they is no more absurd than sexless he. The conservative-traditional "Every student must buy his own books" is silly in countries (like Britain and America) where more university students are female than male. And we go beyond inaccurate to offensive in the case of the New York lawmaker who said "Everyone will be able to decide for himself whether or not to have an abortion."

At the next-to-last ditch, we have the rule "try he or she" trying hard to fit both the traditional (non)-rule and modern sensibilities. I've never seen a usage commentator call this ungrammatical: Everyone must bring his or her homework to class. But there is near universal consensus that it is ugly and awkward, especially when repeated: Each student is expected to bring his or her homework each day, and he or she should be prepared to discuss his or her work in front of the class.

We're forced to conclude, as Mr deBoer does, and as Bryan Garner (a moderate prescriptivist) does, that singular they is "the most convenient solution". And yet since singular they will still annoy many readers, many writers will want to write around the problem. Putting the referent in the plural—"All the students aced their projects"—nixes the troublesome (grammatically singular but semantically plural) each student. Writing around the problem is an unsatisfying solution, since it gives the people who are wrong on the merits the last say. Many readers will react as they did to our advice on the split infinitive: "don't let the bastards win!" But life, unfortunately, is full of unsatisfying solutions. And descriptivists, of all people, should be sensitive to the usage opinions of large minorities. Use singular they in relaxed prose, when you know you're in the company of those who get this right, or if you don't mind annoying a determined and vocal minority.