 If we understand the principles that drive the logic of the system, we may be able to predict that a population of insects will evolve resistance to a pesticide. We may be able to predict that a society that declares war on drugs will lose. Beyond the question of what we can predict, then, Hayek has a further and more precise target: however much we can predict, there is a drastic limit to what we can simply  decide.[2]  No one can decide that people won’t respond in predictable ways to perverse incentives unintentionally created by a central plan, in the same way that no one can decide that insects will not become resistant to an insecticide.