"Gravity is not the result of things falling down but of the earth falling up," according to a trailer park owner named Jim Carter. He believes everything is constantly expanding and the earth itself is doubling in size every 19 minutes-thus, the ground is rushing up to meet whatever you drop. For many years acclaimed science writer Margaret Wertheim has collected the works of "outsider physicists," most without formal training and all convinced they have discovered an alternative theory of relativity, the origin of the universe, and so on. Fifteen years ago she became fascinated by Jim's theories because of his do-it-yourself attitude, the totality of his thinking, and his sense of humor. To build a model to illustrate his theory that "circlon rings" rather than atoms are nature's building blocks, he needed to observe how 3-foot wide smoke rings interacted. His first failed effort to make large smoke rings involved a dog bowl and a sack of gunpowder! Learning from each failure, six months later, with the neighbors gathered in the yard, Jim used a rented disco smoke machine, a huge piece of rubber sheeting, and a rope to send giant white smoke rings sailing across the yard, some of them colliding and bouncing apart like billiard balls. Their movement confirmed his prediction of how his theoretical circlons would behave. Regardless of whether any of Jim's theories are right or not, his story and that of other outsider physicists is fundamental to our understanding of the evolution of science--from natural philosophers who puzzled out the laws of nature using observation and experimentation, to modern professional scientists whose work has grown theoretical and inscrutable, and back to outsider physicists whose creative theories strive to make complicated science accessible to the masses.