"All animals have souls."
Translation:Alle dyr har sjeler.
Not necessarily true, in this sentence 'dyr' is plural and not singular. So you have to use 'sjeler'.
*ninja-edit. Old rule says you should use the singular form, when there's any object or thing you only have one of, like 'sjel'.
But the younger generations today use both singular and plural forms, likely because of English influence.
I also want to add, that my dialect uses both. Confirmed when I talked with my older relatives (50's - 80's).
Isn't this something along with the ever recurring I livene våre? Which is wrong, as each and one of us have only one life. English speakers does say our lives, but in Norwegian it is almost always correct to say Vårt liv (yes there are some strange constellations where it could be correct to have plural lives)
And since no one has more than one soul (awful example sentence) I agree with thevebs. Alle dyr har sjel.
I stand by my original post. Items of which you have only one, remains singular in standard Norwegian, even if you talk about several people having it at the same time (hrm). For younger people it sounds normal to talk of "livene våre" since the English influence is so strong (our lives), but that has still not become correct Norwegian.
http://tux.aftenposten.no/spraak/spraak?action=question=5249 ( add (and-sign)id before the last = to make link work.. )
Another example from the link above "Legen ba tilhørerne ta vare på hjertet sitt" - The doctor begged the audience to care for their hearts. Singular in Norwegian, plural in English. Souls comes in singular.
He questions himself in your link, because a generation ago there was no doubt. While now people widely use both the singular and plural forms more or less interchangeably.
Some of his examples I would also use the singular form, while others I find it just as natural to use the plural form like many other people.
However, if it is in fact a rule. Then you should definitively use the singular form.
I still think both are acceptable, seeing the general population uses both forms. Clearly the old rule is falling out of favor.