Plan B

We sometimes strive to achieve difficult goals when our evidence suggests that success is unlikely—not just because it will require strength of will, but because we are targets of prejudice and discrimination or because success will require unusual ability. Optimism about one’s prospects can be useful for persevering in these cases. With that said, excessive optimism can be dangerous; when our evidence is unfavourable, we should be at most agnostic about whether we will succeed. This paper explores the nature and rational significance of agnostic practical commitments. Most importantly, the rationality of striving against the odds can depend on investing in a plan for failure—a plan B. I aim to make headway on an account of what backup plans are, how they are related to primary plans, and whether the standard norms of plan rationality apply to our agnostic commitments.