One of the best aspects of summer weather is that you’re able to clear your head every now and then with a walk. I’ve recently taken to avoiding taking buses and streetcars whenever possible, allowing me to have such clear moments, away from the clatter, the cell phones, and the other commuters. Sometimes this clarity brings about some ideas worth exploring, such as the following thought experiment:

A few years from now, it becomes increasingly apparent that those born after, say 1980, have ceased to exhibit any signs of biological aging. With that, anyone who falls under this demographic are no longer susceptible to any form of age-related illness or condition, both physically and mentally. Everyone’s biological age caps off at around 35; their chronological age increases, but their bodies stay relatively in the same condition, and their minds stay similarly as sharp. 

This is starting to sound like the opposite scenario as to the situation posed in the novel (and recent film) Children of Men by P.D James. In the film, which is also set in the near future, all the women of child-bearing-ages inexplicably lose their fertility, resulting in mass hysteria, radical social and govermental upheavals, and an aging populace with no younger generations to replace them: in other words, humanity collectively dying of old age, and losing its mind along the way.

Let me expand upon my scenario a bit more. (I think we’ll begin to see more and more similarities to Children of Men as we develop this idea, at least in terms of how society and humanity react to this phenomenon). So everyone on the planet born after 1980 seems to cease aging at ~35 biological years. No scientific endeavor can explain it. Children are born, they grow, reach adulthood, and stay put in their mid-thirties; no grey hairs, no senility, no loss of sensual acuity. In addition, let’s assume that the entire world is affected, not just those in countries blessed with good nutrition and comfortable climates. Sure, people will still die of malnutrition, plague, armed conflicts, and environmental catastrophes - but no one is dying of old age. Theories aimed at explaining this global condition revolve around dietary or environmental changes occurring around the year 1980, which had gone unnoticed at the time, and thus affecting only newborns born from that year onwards. However, just like in the case where the whole world suddenly becomes infertile, no one can convincingly explain why anyone under 35 is poised to live indefinitely. 

Today many futurists envision a near future in which radical life extension is possible, and eventually readily available. Inventor and futurist Ray Kurzweil, for one, has gone to great lengths to ensure his own longevity: with meticulous medical and dietary regiments, he has apparently stalled his biological again process for the last several years. He promises to do this until new innovations in biological, nanotech, and robotic research can provide even longer life extensions. Similarly, in the field of biomedical gerontology, researchers such as Aubrey de Grey is exploring the idea of regenerative tissue, to eliminate all forms of age-related tissue-damage, thus providing indefinite lifespans. 

Such therapies will undoubtedly be costly at first, and available only to the privileged classes, however it would only be a matter of time before the entire planet could enjoy such longevity. What I’m curious about is this: what then? What happens when the entire world has the ability to live as long as they want - to stay effectively the same biological age. I suppose this is more a general case of my thought experiment - that in which everyone (inexplicably) loses any signs of tissue decay. 

In my thought experiment, the older generations eventually die off, leaving a world of thirty-somethings (and younger) behind. Males stay reproductively viable, while obviously females still have a set number of ova (however menopause would  have no age-related effects - simply a halt in the menstrual cycle). Despite this - would humans still seek out sex? One could argue that all sexual intercourse, even sex sought out solely for pleasure, and not reproduction, is driven by an underlying instinct to ensure our genetic survival. In the case of ensured genetic survival through indefinite lifespans, would we lose this instinct altogether and stop having sex? In this sense, immortality may be its own form of population control: there’s no need to worry about the world getting too crowded: while nobody is dying, nobody new is showing up either. 

If I’m wrong - then we may start seeing another form of catastrophe. Remember those social and governmental upheavals? The mass hysteria? Someone’s going to need to control a population that won’t die off, with new generations adding to the pile. One would hope that with age comes wisdom, and that an aged society may formulate a wizened and ethical form of population control. Otherwise, the world could spiral into a system of harsh anti-reproduction policies, such as those used today in China. 

I’m suggesting here that the purpose of life is to create new life. If there is no need (or ability) to create new life, life loses its purpose. Hence, an existential catastrophe among the immortals.

Footnote: I imagine that I am neglecting a whole spectrum of social, cultural, and religious reactions to the thought experiment - so I ask you, dear reader, to fill in the blanks.