Learning to control dynamic systems with unknown models is a challengi
ng research problem. However, most previous work that learns qualitati
ve control rules does not construct qualitative states; a proper parti
tion of continuous-state variables has to be designed by human users a
nd given to the learning programs. We design a new learning method tha
t learns appropriate qualitative state representation and the control
rules simultaneously. Our method can aggressively partition the contin
uous-state variables into finer, discrete ranges until control rules b
ased on these ranges are learned. As a case study, we apply our method
to the benchmark control problem of cart-pole balancing (also known a
s the inverted pendulum). Experimental results show that our method no
t only derives different partitions for the cart-pole systems with dif
ferent parameters but also learns to control the systems for an extend
ed period of time from random initial positions.