Bryan Garner’s Usage Tip of the Day today is about none. Singular, or plural? Garner offers the clearest explanation I know of how to decide:
None = (1) not one; or (2) not any. Hence it may correctly take either a singular or a plural verb. To decide which to use, substitute the phrases to see which fits the meaning of the sentence: “not one is” or “not any are.”A further comment:
Generally speaking, “none is” is the more emphatic way of expressing an idea. But it’s also the less common way, particularly in educated speech, and it therefore sounds somewhat stilted. The problem is exacerbated by the unfortunate fact that some stylists and publications insist that “none” is always singular, even in the most awkward constructions.Fowler’s Modern English Usage (1926) recognized that none can be singular or plural: “It is a mistake to suppose that the pronoun is sing. only & must at all costs be followed by sing verbs, &c.” Garner’s comment is likely a tactful criticism of The Elements of Style. The 1959 edition says that none “takes the singular verb,” period. The 1972 edition acknowledges that none can be singular or plural. E. B. White added and then amended the note on usage for none. William Strunk Jr.’s 1918 Elements says nothing about the word.
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