I want to know the answer to the following question:
What unpredictable feature of the world did Popper say refuted historicism?
All the background I'm provided with is that "Since the growth of human knowledge is a causal factor in the evolution of human history, and since "no society can predict, scientifically, its own future states of knowledge", it follows, he argued, that there can be no predictive science of human history.". Is that enough to answer the question?