Yet we cannot imagine, in our wildest dreams, exactly how our grandchildren will live their daily lives.
My father died when I was thirteen and he lived a life his parents could probably envisage. He saw the development of flight and of automobile travel, improvement in farming, the telephone, and electricity. All of these developments were, if not available, at least imagined by his parents' world.
But, I don't think he could picture my daily life if he were able to make a visit to the present day. How would I explain to him personal computers, on-line banking, hackers, reading his favourite Zane Grey on a tablet, space expeditions to Mars, or Skyping someone across the world? I think he'd take one uncomprehending look around him, say "I think I'll wake up from my dream soon" and close his eyes to head for home.
Now flash forward to our grandchildren's time. What totally unconceivable (to us) things might be part of their world? Will they colonize other planets? Will space travel be as commonplace as a flight to Europe? Will they be implanted at birth with a personal epidermal computer? Will our continents flood and change through climate disasters? Anything we speculate about will probably be superceded by something even more remarkable that doesn't even cross our minds. Who knows, maybe they'll travel back in time to tell us all about it.
One thing I can probably predict. Platform shoes and bell bottoms will make at least one more resurgence into fashion in their lifetime. They are the only truly indestructible things we know.