In a lot of countries, we're also seeing the age of having first child go up. Inevitably, if people are going to have fewer children, the population there will start getting older. Aging is inevitable. It will happen all over the world. There are no exceptions. And I believe most countries are not adapting very well. We're not successfully changing our institutions and mindsets to deal with population aging. One should invest much more in health to keep a large share of the population able to contribute"
On 15 November the world’s population reached 8 billion, according to the UN. Much of that growth is because we’re living longer. As a species we will continue to age, but eventually stop growing. The UN predicts that in the next century humanity will begin to go into decline. So what happens when societies get older and smaller – a problem some countries are already encountering? Ian Sample speaks to Prof Vegard Skirbekk about how humanity got here, and how we prepare for future demographic change. Help support our independent journalism at
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