Letters 79.11

Already much of the task is accomplished; nay, rather, if I can bring myself to confess the truth, not much. For goodness does not mean merely being better than the lowest. Who that could catch but a mere glimpse of the daylight would boast his powers of vision? One who sees the sun shining through a mist may be contented meanwhile that he has escaped darkness, but he does not yet enjoy the blessing of light.

Seneca, Letters to Lucilius 79.11, translated by Richard Mott Gummere