Calvin and Hobbes by Bill Watterson for August 17, 1986
Calvin: You know, Dad, it disturbs me that this wagon has no seat belts and wouldn't survive a 30 mph impact with a stationary object. Dad: Um..why do you bring this up? Calvin: Oh, no reason. Want to help me test the theory of relativity? Hobbes: Sure. Calvin: The idea is that the faster we go, the slower time goes. Hobbes: Gotch. It's 10:23. Calvin: What time is it now? Hobbes: 10:24. Go faster. Calvin: We're going pretty fast! What time is it? Hobbes: 10:25. Time still hasn't stopped. Calvin: Has time stopped now? Hobbes: No, just my heart. Calvin: Well, it looks like Einstein's a fraud, wouldn't you say? Hobbes: No, he's right! Look, my watch isn't going at all anymore!!