Our ageing world isn't a catastrophe. It's a triumph.

The rise in the number of the old is a massive human success story: life expectancy increases because of better education, greater wealth, lower infant mortality, better healthcare, less disease, the reduction of armed conflict, and the development of technology and its application in pursuit of good. It is, frankly, insane to look at an ageing population and not rejoice. Why do we even have a concept of public health, of co-operation, of sharing knowledge, if not to extend life, wherever we find it? The problem, then, is not age as such but the proportion of the aged. Guardian