He said the Earth is like a large mechanical device that will survive only if people living on it know how to operate it correctly.

VOA: special.2010.05.30

now I'm really fantastic at drawing this mechanical device, but you can imagine that dropping a weight can cause a paddle wheel to turn.

机械装置的时候,我真的很着迷，你可以想象,当重物掉落的时候会带动桨轮旋转。

麻省理工公开课 - 热力学与动力学课程节选