It's one of those time-wasting questions that would be good for a long car trip, when I Spy gets too boring but you want to keep conversation clean enough for your Nan to play along, too.
As human beings in 2015, what aspects of our lives today will we reflect on in the future with befuddlement and awe?
There's the obvious stuff and actually it's fun to get Nan going because she'll remember some perfectly ridiculous examples from only a few years back.
She might recall the way sportspeople used to smoke cigarettes in the half-time break or when a trip to Australia took 10 days at sea. She might bring up domestic life before Fisher & Paykel or when it wasn't altogether alarming to see a Prime Minister drunk on TV.
You'll counter with some modern examples of stuff that will soon seem totally absurd: sleeve tattoos and those earlobe-stretching piercings, paddle boarding, Robin Thicke singles and bikini waxes for all (Don't act so naive, Nan).
The conversation might turn deep.
After discussing low-riding jeans, capital gains taxes (or lack thereof) and gluten freedom, you'll turn to more pressing examples about fossil fuels and carbon dioxide.
"Nan, won't it seem absolutely absurd that once upon a time we actually burned coal?"
And maybe this week if you were playing the game and were looking to the news for inspiration, you'd offer up an even darker example: maybe one day it won't be acceptable for any government to punish its criminals by putting them to death.
Maybe Indonesia will change its laws. Saudi Arabia, too. Maybe America and the other 30-odd countries that "actively" practise the ultimate punishment might grow uncomfortable with just how primal, medieval, how grossly animalian state-ordered execution really is.
Would we look back at capital punishment with bewilderment? The same way we question nowadays how anyone ever thought the world was flat?
Probably not. Because for all our fashions and advances, politics and growth and change, in some departments we really haven't progressed in tens of thousands of years.
Depressing, that.