In second grade I asked my mom how Santa could make so many public appearances on such a tight schedule. Not every Santa was the actual Santa, she said, they were just guys that the real Santa asked to help him out. How logical, I thought, Santa is a busy man. That’s the sort of loving lie parents tell their kids about Santa. It’s a pretty easy lie to tell. An ingrained part of our culture , talking to kids about Santa feels, if you think about it, weirdly normal. Letting children use their imaginations to conjure this image is healthy, psychologists argue , saying that the practice is what will later help them dream up inventions and other big ideas. Similarly, fairy tales have been shown to be an effective and more meaningful way to teach children morals; the naughty-or-nice list becomes a guide to growing up to be a decent person. Even if your goodness is derived from a fear of not receiving a Furby. Yet, about 54 perc...