I'm 31, with a toddler. I can't compare anything I do with the joy she gets out of the most mundane things. The first time she tasted chocolate? Blows me going to Alinea out of the water.
I'm not trying to disagree with you, I have a 7 month old son, but what about the joy you felt seeing her being born? I know that isn't a mundane thing and that you likely won't have it but a few more times but there are experiences that children can't have, that are, at least, as transcendent as a child's first taste of chocolate.
But that's precisely the thing. In a stable population, births per year are inversely proportional to life expectancy. So whatever joy seeing a child born brings to people, there will necessarily be less of that per year aggregated over the whole society. A society where everyone lives longer is necessarily one with a smaller proportion of joyful idealistic children and a higher percentage of cynical jaded older people.
