Peter

A is a country where men have four wives and people who happen to be male but not good at getting wives are not defined to be "men" ("boys" perhaps?). Which isn't very fair, but would at least allow for one of these statements to be entirely true. Of course v.v. works fine also (A is a country where marrying means you are no longer "a man" but rather "a husband" or something).

Apparently in practice the very rich keep four wives in style, the very poor have four wives all with nothing and the middle classes have only one so as to better keep up with the Joneses (or local equivalent).