Against these considerations, the clever ones will propose that if we could do away with death, we would do away with the need for posterity. But that is a self-serving and shallow answer, one that thinks of life and aging solely in terms of the state of the body. It ignores the psychological effects simply of the passage of time – of experiencing and learning about the way things are. After a while, no matter how healthy we are, no matter how respected and well placed we are socially, most of us cease to look upon the world with fresh eyes. Little surprises us, nothing shocks us, righteous indignation at injustice dies out. We have seen it all already, seen it all. We have often been deceived, we have made many mistakes of our own. Many of us become small-souled, having been humbled not by bodily decline or the loss of loved ones but by life itself. So our ambition also begins to flag, or at least our noblest ambitions. As we grow older, Aristotle already noted, we “aspire to nothing great and exalted and crave the mere necessities and comfort of existence.” At some point, most of us turn and say to our intimates, Is this all there is? We settle, we accept our situation – if we are lucky enough to be able to accept it. In many ways, perhaps in the most profound ways, most of us go to sleep long before our deaths – and we might even do so earlier in life if death no longer spurred us to make something of ourselves.
In contrast, it is in the young where aspiration, hope, freshness, boldness and openness spring anew – even when they take the form of overrunning our monuments. Immortality for oneself through children may be a delusion, but participating in the natural and eternal renewal of human possibility through children is not – not even in today’s world.
Leon R. Kass – Life, Liberty, and the Defense of Dignity: The Challenge for Bioethics p.272