A few people have asked what the title of this blog means. In a lull between activities during the camp for post-tenth graders that I’m working with this week, one of the students asked me to tell them a story. So I told them the Indian folktale of the eighteenth elephant, which goes like this:
Once there was a king who had seventeen royal elephants — beautiful elephants, bedecked with jewels, draped in silk, smart and strong. The king died, and left the elephants to his three sons, with instructions that the oldest son should get half of them, the middle son one-third, and the youngest one-ninth. The princes were confused. Half of seventeen? A third? A ninth? What were they supposed to do? Cutting up an elephant was of course unthinkable. The king’s chief minister came upon them, puzzled and sad. “Don’t worry,” he said. “You’re nice kids, and I’ll give you one of my elephants.” And so he brought in one of his, also quite stylish and bejeweled.
The eldest son happily led nine elephants away (half of the bunch). The middle son took six. The youngest one noted that two is one-ninth of the total, and took his two. The princes together had 9+6+2 = 17 elephants, and the chief minister took his own elephant back to its stable, and they all lived happily ever after.
I like this story a lot. (My 8-year old does also.) I’ve brought it up in classes several times, since it highlights a common approach to solving physics problems, of inserting some sort of assumption or framework that makes the problem easier, and then removing it afterwards. For example, in my Physics of Solar and Renewable Energy Class, we figure out how wind power scales with wind speed, imagining wind as traveling in little cubes, finding that the answer doesn’t depend on the size of the cubes, and then sending the cubes back to their stables.
Perhaps more relevant for today, the high school students liked the story a lot as well, and we continued to chat about a variety of things. Often, I think, I over-prepare activities, and would perhaps be better off (and less exhausted) sitting and telling stories…