Q: I’m confused by this quote from Stieg Larsson’s thriller The Girl with the Dragon Tattoo (2008): “Blomkvist had often wondered whether it were possible to be more possessed by desire for any other woman.” The use of the plural “were” strikes me as awkward. Wouldn’t it be more natural to use the singular “was”?
A: In this sentence, Larsson (or, rather, his translator) was using the subjunctive mood (“whether it were possible”) instead of the indicative mood (“whether it was possible”). In the subjunctive, “was” becomes “were,” and the switch has nothing to do with plurals vs. singulars.
Now for the real question: Was it appropriate for the translator (Larsson wrote in Swedish) to use the subjunctive in the sentence you quoted?
English speakers use the subjunctive mood (instead of the normal indicative mood) on three occasions:
(1) When expressing a wish: “I wish I were taller.” [Not: "I wish I was taller."]
(2) When expressing an “if” statement about a condition that’s contrary to fact: “If I were king …” [Not: "If I was king ..."] Larsson is extending this to a “whether” statement, since “whether” sometimes has the meaning of “if.”
(3) When something is asked, demanded, ordered, suggested, and so on: “I suggest he get a job.” [Not: "I suggest he gets a job."]
I wrote a brief explanation of the subjunctive for the blog a few years ago.
So, was Larsson’s translator justified in using the subjunctive? I don’t think so.
It’s conceivably possible that Blomkvist might one day be more possessed by desire for another woman. So, there’s no need to use the subjunctive here and Larsson should have written “whether it was possible.”
The subjunctive is only appropriate when a statement is clearly contrary to fact. For example: “Blomkvist had often wondered if [whether] he were dead.”