The West is dying because we're over-regulated, overtaxed, and uncertain about the future. Nobody wants to invest in a child! Simply put, why have children if you're already going to spend your life working for slightly above subsistence? Almost nobody gets rich, so we wait till we're stable, and by that time, we're too old to have many children. In addition, we have to deal with the question of "why should I get married when there is tinder?" The West hate themselves and many are starting to withdraw from society, just like the Japanese of today or the Romans during the fall. Welfare is a large part of this, as people become entranced by the "circuses" of the day such as video games, Netflix, and television sports. We have culture wars that are pulling us apart.. This is just another symptom of the fall of New Rome. Intelligence is not the reason we don't have kids. It is simply an indicator that the people of the West are smart enough to not have kids until they're older and have stable incomes.