It depends.......If the first wife of the man doesnt have any problem with him marrying again,then its okay......He can marry how muchever he wants if his other wives agree.....But,If he is cheating her atau dumping her for the saat lady,then its wrong...he should be punished....atleast he should divorce the first one b4 marrying the second...so that she can also have a life.....well,this is my opinion:)
It depends. If everyone agrees on it, takes responsibility, set up rules, and it was made legal, than no. If it's illegal in the country, likley to cause problems, atau done serialy, than yes.