An unpredictable system is not necessarily an uncontrollable one

From the article:

Controlling the long-term evolution of a system is different, and in many ways easier than, predicting that long-term evolution.

The key is that our controller doesn’t have to decide all of its future actions up-front; it will be able to make use of additional information as time goes on. We don’t need to be able to predict where the system’s current state will carry it in the long term, or know the current state to infinite precision, as long as we can get frequent measurements that keep the controller up-to-date on deviations.