Close your eyes and imagine someone from a younger generation who you really care about. Now imagine them 30 years in the future. Then imagine it's their 90th birthday. They are surrounded by family and friends, ready to give their birthday speech. With a glass in hand, they look over and see a photo of you, their departed ancestor. They decide to tell the room what they learned from you.
When philosopher Roman Krznaric imagined his 11-year-old daughter, he says "it shook me up".
"I realised she might have kids or grandkids who could live well into the 22nd century, and we are only two steps away from that."
Over the past year he has conducted the experiment with scores of people for his new book, The Good Ancestor, and found many participants "choked up". It goes against the belief that we are inherently selfish, short-term thinkers.
Instead, Krznaric believes, we are trapped in the tyranny of ''now'', driven by 24-hour rolling news, one-click purchasing and four-year political cycles.
But with a simple change in perspective, Krznaric says, "we can get out of our egotistical shell" for the long-term benefit of society.
Krznaric, a bestselling author, writes about the power of ideas to change society. He is a founding faculty member of The School of Life and has set up the world's first Empathy museum.
The Good Ancestor has received a hearty endorsement from U2 guitarist The Edge ("this is the book our children's children will thank us for reading"). In it, Krznaric urges readers to consider the bigger picture.
"Future generations have no vote and no voice, yet our actions affect them," he told the Sunday Independent. "If I was advising the Irish Government, I would say look around the world. There are really cool models you can draw on.
"In Wales they have a future generations commissioner, Sophie Howe. Her job is to scrutinise legislation in all areas for its impact on 30 years from today. Maybe Ireland could follow suit."
He would "encourage the Irish Government to look at a movement in Japan called 'future design'."
"There they are trying to reinvent democracy and make it more long-term. They invite citizens from a city or a town to make decisions about the place they live. They split them into two groups. One is the residents of the present day and the other is ''residents from 2060''. It turns out the residents from ''2060'' come up with much more radical plans for environmental, employment and education policy.
"When they asked the residents from the present if they were willing to pay more money for a better water system in 50 years, for example, they didn't want to invest that money. But when they asked the group from 2060, they were more than willing, even when they didn't have kids. Ireland could take its citizen assembly model a step further and incorporate this. Have half the people thinking specifically about future generation issues. It has been very successful in Japan and a really powerful way of doing politics."
Krznaric also writes about ''cathedral thinking'', the practice of envisaging and embarking on projects with time horizons stretching decades and even centuries into the future. Medieval cathedral builders began their work while knowing they were unlikely to see construction finished within their lifetimes.
But cathedral thinking has taken other forms. "We can see it in public works projects," Krznaric explains. "In Victorian London sewers were built in the 1860s after the 'Great Stink' of 1858. The stench was so bad, MPs couldn't breathe in the House of Parliament. They passed crisis legislation and spent 18 years building an underground sewage system that is still used today. Perhaps your Government could take inspiration. In Dublin the water supply system is under constant stress and produces regular shortages. It has scarcely been upgraded since the 19th century. A bit of cathedral thinking could go a long way to help remedy the situation."
There are easier ways to embrace long-term thinking, he believes.
"I go with my kids to the local beach and we hunt for fossils. There we can hold a belemnite, a creature that's 195m years old and the kids and I both look in wonder.
"Or we visit an ancient tree that's a thousand years old. Anything that puts us in touch with a deep sense of time.
"It's a feeling you can't buy off the shelf. But it's something we can definitely work on."