When Japanese finance minister Taro Aso recently urged the elderly to “hurry up and die”, few heeded his advice. In fact, the Japanese insist on living longer than any other race. The politician, who is also the deputy prime minister, went on to ask:

“Why should I have to pay taxes for people who just sit and do nothing but eat and drink?” He made it clear to his audience that he had asked his family to make sure he was not put on life-support when he was preparing to enter the heavenly Geisha Palace. As he is now 72, he may not have very long to wait, even given Japanese longevity.

Certain tribes of Native Americans – it’s no longer politically correct to call them Red Indians — agreed with Mr Aso. While they did not pay taxes, they encouraged the elderly who no longer contributed to the tribe to go off to a remote corner and quietly starve to death.

At the last census in 2010, the Japanese population stood at just over 128 million, of whom fully a quarter are over 65. But the truly alarming trend is that the population is falling by around a million a year. With a birth rate much lower than the replacement rate of 2.1 per cent, Japan’s population is expected to be around 87 million in 2060, of whom 40 per cent will be over 65.

While the government is understandably worried about these depressing projections, many Japanese see the positive side of an ageing country. For them, fewer people mean a less crowded island, and lower pressure on resources and the environment. Incidentally, they don’t view their declining numbers as a Western plot to reduce the Japanese population.To cope with a decreasing workforce, Japan has long been a world leader in robotics. While it pioneered the use of industrial robots now in use in factories worldwide, it has now introduced these autonomous machines in homes and offices for a wide variety of tasks. Some are mechanical animals that can be pets for lonely people but without the hassle of caring for flesh and blood creatures. Others are friendly machines that can display emotions. Domestic robots can clean the house and mow the lawn.

Scientists are hard at work refining artificial intelligence and speech recognition software to improve robotic performance. The Holy Grail remains an all-purpose robot that can be programmed to do a wide variety of tasks. Driven by demography, the technology may usher in a new world where robots are as commonplace as cars are today. Indeed, self-driven cars are now expected to take to the roads by the end of this decade with the likes of Google having invested billions in developing the technology.

But Japan is not alone in this demographic crisis: Russia had a population of 148.7 million in 1991which fell to 143 million in 2012. This fall is largely due to an extremely high death rate of 14.3 per thousand, compared to 8.4 in the USA. Although the reasons for this are not entirely clear, many experts ascribe this high mortality rate among men to alcohol abuse.

In Italy, fertility rates plunged after the seventies, but have risen to 1.4 per woman recently. Even this is well below the replacement rate of around 2.1 children per woman. Currently, 21.6 per cent of all Italians are pensioners, adding to that country’s economic woes.

To make up this fall in numbers, Italy has resorted to large- scale immigration to man its farms and factories. The number of immigrants has nearly tripled to 3.7m in 2011 from 1.3m a decade ago. These are official figures for legal migrants; the actual number will be far higher, given the steady flow of illegal workers flooding into the country. The legal migrants are now 6.3 per cent of the total population of just over 60m.

Despite these trends in developed countries, many regions continue to witness a rise in population. Our planet now supports over seven billion people, and this number is expected to continue increasing to nine billion in 2050 when it will finally stabilise.

In Pakistan, the subject is barely discussed any more, despite the enormous problems it has led to. No TV talk show is devoted to demography, beyond inviting some ignorant cleric to fulminate against western plots to limit the Muslim population through family planning. No politician dares mention the subject. Indeed, successive governments since Zia have largely ignored the issue, fearing a backlash from the country’s small but vocal and violent religious parties.

But ignoring the problem won’t make it go away. According to the website www.newgeography.com Pakistan’s population is now 197.4m, up by 62.7m from the 1998 census. The average annual increase works out to 3.2 per cent, compared to 2.6 per cent for India, and 2.2 per cent for Bangladesh. In fact, this rate is the highest for any country outside Sub-Saharan Africa. The size of the average household is 6.8, far larger than other comparable countries.

Over the same period, Karachi has grown at an even faster rate, with 21.2 million people living there, compared with 9.8m at the turn of the century. These numbers are immediately transformed into flesh and blood as soon as you step out of your home: the whole country seems absolutely overrun with an increasingly younger population.