Emerson argues that significant achievement usually requires more than competence or careful planning. By “enthusiasm”, he points to the energy, conviction and sustained interest that enable a person to pursue demanding aims. Great work often involves uncertainty, difficulty and repeated effort, making strong personal engagement an important source of persistence.

Within Circles, the statement fits Emerson’s wider emphasis on growth, movement and the willingness to exceed established limits. Enthusiasm helps propel individuals beyond passive acceptance of existing conditions and towards new possibilities. The claim is deliberately broad and should not be read as suggesting that enthusiasm alone guarantees success. Skill, judgement, opportunity and sustained work may also be necessary. Emerson’s central point is that major achievement is difficult to separate from the intensity of purpose that motivates people to attempt, continue and develop demanding work.