"I suppose they're all just as much alive as we are," she said thoughtfully. "They marry"--I looked at my limpet with a new interest--"and bring up families and go about their business, and it all means just as much to them as it does to us." "My limpet's business affairs mean nothing to me," I said firmly. "I am only wrapped up in him as a sprinter." "Aren't you going to try to move him again?" "He's not quite ready yet. He still has his suspicions." Celia dropped into silence. Her next question showed that she had left the pool for a moment. "Are there any people in Mars?" she asked. "People down here say that there aren't. A man told me the other day that he knew this for a fact. On the other hand, people in Mars know for a fact that there isn't anybody on the Earth. Probably they are both wrong." "I should like to know a lot about things," sighed Celia. "Do you know anything about limpets?" "Only that they stick like billy-o." "I suppose more about them _is_ known than that?" "I suppose so. By people who have made a specialty of them. For one who has preferred to amass general knowledge rather than to specialize, it is considered enough to know that they stick like billy-o." "You haven't specialized in anything, have you?" "Only in wives." Celia smiled and went on. "How do you make a specialty of limpets?" "Well, I suppose you--er--study them. You sit down and--and watch them. Probably after dark they get up and do something. And of course, in any case, you can always dissect one and see what he's had for breakfast. One way and another you get to know things about them." "They must have a lot of time for thinking," said Celia, regarding my limpet with her head on one side. "Tell me, how do they know that there are no men in Mars?" I sat up with a sigh. "Celia, you do dodge about so. I have barely brought together and classified my array of facts about things in this world, when you've dashed up to another one. What is the connexion between Mars and limpets? If there are any limpets in Mars they are freshwater ones. In the canals." "Oh, I just wondered," she said. "I mean"--she wrinkled her forehead in the effort to find words for her thoughts--"I'm wondering what everything means, and why we're all here, and what limpets are for, and, supposing there are people in Mars, if we're the real people whom the world was made for, or if _they_ are." She stopped and added, "One evening after dinner, when we get home, you must tell me all about _everything_" Celia has a beautiful idea that I can explain everything to her. I suppose I must have explained a stymie or a no-ball very cleverly once. "Well," I said, "I can tell you what limpets are for now. They're like sheep and cows and horses and pheasants and--and any other animal. They're just for _us_. At least so the wise people say." "But we don't eat limpets."