In rebus naturalibus videmus contingere quod omne malum sub ordine alicuius boni concluditur; sicut corruptio aeris est ignis generatio, et occisio ovis est pastus lupi.
"In natural things we see it happen that all evil is included under the ordering of some good; as corruption of air is generation of fire, and the slaughter of a sheep is the feeding of a wolf."
Summa contra gentiles 3.140 n. 5
