For these reasons changing values has particularly great significance from a longterm perspective. Looking to the past, we see that such changes have had an enormous impact on the lives of billions of people. Looking to the future, if we can improve the values that guide the behaviour of generations to come, we can be pretty confident that they will take better actions, even if they’re living in a world very different from our own, the nature of which we cannot predict.

This suggests that, as longtermists, when trying to improve society’s values, we should focus on promoting more abstract or general moral principles or, when promoting particular moral actions, tie them into a more general worldview. This helps ensure that these moral changes stay relevant and robustly positive into the future.

When confronted with the empirical and evaluative complexity that faces us, it can be easy to feel clueless, as if there’s nothing at all we can do. But that would be too pessimistic. Even if we’re walking backwards into the future—and even if the terrain we’re walking on is unexplored, it’s dark and foggy, and we have few clues to guide us—nonetheless, some plans are smarter than others. We can employ three rules of thumb.

These three lessons—take robustly good actions, build up options, and learn more—can help guide us in our attempts to positively influence the long term.

Most of what will be important in the future is outside our knowledge; it exists only in the future. The direct approach demands a capacity for prediction that we can never possess.