I read someone&#x27;s demographic observation that children are an asset in rural areas and a liability in urban areas. It&#x27;s not clear that you could easily convince small-scale rural farmers in an area that wasn&#x27;t affected by human population pressures that having lots of kids was a bad idea for the future. (At best, they might say &quot;OK, when there are so many people that they&#x27;re crammed together in cities, maybe it will be possible for the people of the future to want to have smaller families&quot;.)