Rocking chairs are by far the coolest chairs. Someone should invent a rocking sofa. I'd buy it. There's alot of physics that goes into the rocking back and forth of a rocking chair. The motion is started by the person sitting in the rocking chair. Utilizing the strenght of their legs they push against the ground. This causes the chair to rock upwards. Then the chair rocks downward due to the curved nature of the chairs base and newton's second law, every force has an equal opposite force. Thus the rocking chair begins its journey rocking back and forth. Thats why rocking chairs are dope.