Our grandchildren aren’t stupid. Their mental equipment isn’t inferior to ours. They just live in a different world, one which no longer belongs to us even though we helped create it. It’s theirs now, and whatever we imagine, we’re no longer in any position to judge them. Likely they’ll be fine, but if they turn out not to be fine, it’s going to be very hard to show how listening to us would have made the slightest bit of difference.