Keller presents optimism as more than a pleasant outlook. She describes it as a form of confidence that makes purposeful action possible. In this sense, hope provides the expectation that effort can lead somewhere worthwhile, while optimism helps sustain the willingness to act despite uncertainty about the outcome.

The statement does not imply that optimism alone produces achievement. Rather, it identifies hope as an important condition for attempting difficult work, persisting through setbacks and imagining improvement. Without some belief that progress is possible, people may lack a reason to begin or continue their efforts. Keller therefore connects an inner attitude with practical consequences: optimism can support action, while hope gives that action direction. The quote fits her broader argument in Optimism that constructive beliefs matter partly because of the conduct and effort they encourage in everyday life.