Samuel Smiles Quote

It is not eminent talent that is required to ensure success in any pursuit, so much as purpose-not merely the power to achieve, but the will to labour energetically and perseveringly. Hence energy of will may be defined to be the very central power of character in a man-in a word, it is the Man himself.

Self-help: With Illustrations of Charakter, Conduct and Perseverance (ed. 1866)