The Big Bang Theory
“Leonard, in the the world of theoretical physics, you never finish; so much is unprovable. But when I was studying that railway guide, it was so tangible and so satisfying that something just clicked. Then it clacked. Then it clicked, then it clacked, click-clack, clickety-clack and here we are. (imitates train whistle): Whoo-whoo!”
- Sheldon Cooper (Jim Parsons) explaining to Leonard Hofstadter (Johnny Galecki) and Howard Wolowitz (Simon Helberg) why he wants to leave physics.