Importance is a property of entities that matter or make a difference. For example, World War II was an important event and Albert Einstein was an important person because of how they affected the world. There are disagreements in the academic literature about what type of difference is required. According to the causal impact view, something is important if it has a big causal impact on the world. This view is rejected by various theorists, who insist that an additional aspect is required: that the impact in question makes a value difference. This is often understood in terms of how the important thing affects the well-being of people. So on this view, World War II was important, not just because it brought about many wide-ranging changes but because these changes had severe negative impa