I’ve thought about that a lot. A few weeks ago Hobbes ate Calvin’s sandwich at the bus stop. Calvin didn’t know it until he got to school and his lunch bag was empty. I thought and thought and finally decided that Calvin ate it himself. What about Hobbes getting home? Maybe Hobbes is there when he isn’t there and then disappears when Calvin wants him to. Or maybe there is no explanation. Maybe those kinds of puzzles aren’t puzzles at all in Calvin world.
You have to give something to get something.