 Natural selection operates on mutations, making the path of natural selection unpredictable, regardless of how well we understand the underlying principles. To Hayek, social and cultural evolution are much the same: driven by innovation, fashion, and various shocks that “mutate” people’s plans in unpredictable ways with unpredictable results. The system may be more or less logical. Most things seem in retrospect to have happened for a reason. Yet, however logical the system may be, its logic does not render the system deterministic. We can make predictions in the broadest sense, such as when we say that increasing the money supply causes prices to rise, other things equal, but we have no basis for predicting the fine details. The system is technically chaotic, to such a degree that even something as straightforward as next week’s stock prices will always remain a matter of guesswork even for experts. (See the entry on  chaos.)