Definition of insanity is arguing with serious idiots. A regular idiot would understand that if you have more than approx 2 children you are contributing to the destruction of our planet. Complex arguments not required. If they don’t agree then they are probably serious idiots - one who will twist the facts to match the decision they already made which is they want lots of children for personal reasons. It’s pretty much impossible to argue with somebody who has already made up their mind. Facts are irrelevant.