Thanksgiving evening at home — snow on the ground outside, the hum of the dishwasher in the kitchen, half-eaten pies on the counter.  The “kids” of the family have taken over the living room: my sister, my two brothers, and I. The TV displays a videogame called Minecraft and they pre-emptively defend it to me: it’s more than meets the eye, they say.  When they start playing, I understand their warning.  The graphics are blocky and old-school.  The 1st-person protagonist looks like a lego man. “ Mountains” in this digital world are more like green and brown staircases.  When you approach...