Letters 69.5

Vices tempt you by the rewards which they offer; but in the life of which I speak, you must live without being paid. Scarcely will a whole life-time suffice to bring our vices into subjection and to make them accept the yoke, swollen as they are by long-continued indulgence; and still less, if we cut into our brief span by any interruptions. Even constant care and attention can scarcely bring any one undertaking to full completion.

Seneca, Letters to Lucilius 69.5, translated by Richard Mott Gummere