Guardian: "What's this?" I asked my nephew. He was soon to turn two, and I thought, perhaps, he would be able to identify the plastic toy in my hand as a "dinosaur". "Edmontosaurus", he told me. I checked the label on its foot. He was right.
Just before his fifth birthday, he corrected me on a question of astronomy: "No, Venus is hotter than Mercury. Mercury is closer to the sun, but Venus has poisonous gases which keep the heat in". I used to know that, I remembered, before I grew up and got boring.
It...