The world population is ageing, partly due to greater longevity, partly due falling birth rates. This creates the understandable concern that the historical pattern of younger generations caring for the elderly will come under threat, with more older people and few younger ones to either care for them or contribute towards pension provision.
The increased longevity is unprecedented, with people across the world living much longer in much larger numbers than ever before, due to better nutrition and much improved healthcare. In most countries, the increase is continuing, with no certainty as to the outcome. While the consequence is many more years of active and healthy life, it also means more years of being dependent on some level of care. The generally falling birth rate also contributes, contributing over time to a changing age profile, where the elderly contribute an ever greater proportion of society. Both trends are characteristic of much of the world, not just the most developed countries.
At some point, the trends will presumably cease, though nothing is certain. Longevity will cease to increase and birth rates will stabilise. Certainly, birth rates have ceased to fall in some European countries. The outcome will be a return to a more balanced age profile, though with a large proportion of elderly than is currently the case. Until that point, however, there are adjustments which have to be made to a very different situation than we have experienced in the past.
Longer, healthier lives mean we can work longer. With more flexible working arrangements, more jobs can be done by older workers, enabling them to top up their pensions by working as much or little as they choose. For instance, given training and support, the fit old can care for the infirm older. Much of the additional cost of supporting any increase in the number of older people who are infirm should be offset by the reduced cost of less childcare.
The view that to look after ever more old people we need ever more young people, who will grow old in turn and need yet more still to support them, is an ecologically unsustainable social pyramid scheme, benefiting the present generation at the expense of the next.
The problems of a stable or reducing population are insignificant compared to those certain to be caused by indefinite growth.