Martin Sustrik

But if so, who bears the liability such as demolishing the house before it collapses during an earthquake and blocks the evacuation routes?

Well, if everything is doom and gloom, at least nature benefits when people are removed from the equation, right?

Let's take a look.

Japan has around 10 million hectares of plantation forests, many of them planted after World War II.

These forests are now reaching the stage at which thinning is necessary.

Yet because profitability has declined, expensive domestic timber was largely displaced by cheap imports long ago, and the forestry workforce was greatly reduced, thinning often does not occur.

As a result, the forests grow too dense for light to penetrate.

Little or nothing survives in the understory.

And where something does manage to grow, overpopulated deer consume new saplings and other vegetation such as dwarf bamboo, which would otherwise help stabilize the soil.

The result is soil erosion and the gradual deterioration of the forest.

The deer population, incidentally, is high because there are no wolves, the erstwhile apex predators, in Japan.

But few people want them reintroduced.

Instead, authorities have extended hunting seasons and increased culling quotas.

In an aging and depopulating countryside, however, there are too few hunters to make use of these measures.

And so, this being Japan, robot wolves are being deployed in their stead.

Finally, care for the elderly is clearly the elephant in the room.

Ideas abound.

Intergenerational share houses where students pay reduced rent in exchange for being good neighbours.

Projects combining kindergartens with elderly housing.

Denmark's has more than 150 co-housing communities where residents share meals and social life.