Book VIII · 15
Remember that as it is a shame to be surprised if the fig-tree produces figs, so it is to be surprised if the world produces such and such things of which it is productive; and for the physician and the helmsman it is a shame to be surprised if a man has a fever, or if the wind is unfavorable.
Marcus Aurelius, Meditations VIII.15. Translated by George Long (1862). The Stoic Library.