An apparently
simple set of pendulums is given an initial twist. One's intuition
says that the resulting motion of this simple system should be,
if not simple, at least predictable. Intuition doesn't work with
this device though, and its motion is an extremely complicated,
and somewhat whimsical, twisting and turning that defies the predictive
powers of physics. The motion of the device is chaotic. If the initial
conditions are truly identical, the pendulum will repeat itself
exactly. Chaotic or nonlinear motion occurs whenever a small difference
in the initial conditions make a large difference in the outcome.

