If a possessive noun, which is plural, is preceded by "each", then should it use the singular or plural possessive form?
For example, which of the following is correct?
- spend time in each other's presence
- spend time in each others' presence
Each other is singular, so the correct possessive is each other's.
I found some controversy on this on the web because each other implies that there are multiple people involved, hence people think it is plural and should be written each others'. This, however, is wrong as each is always singular.
You may find that style guides say that it must be other's, but both can be defended, other’s because presence is singular, others’ because there is a degree of mutuality in the state described. As Pam Peters put it in ‘The Cambridge Guide to English Usage’, ‘the formal grammar of words and the notional grammar of the underlying semantics are at loggerheads.’
If you’re feeling adventurous, you can omit the apostrophe altogether.