Third sense: natural as what one has from birth, whether good or not
Natural can also mean what each person has from birth, whether it is good for nature, suited to it and in keeping with natural appetite, or not. In this sense too, he admits, immortality was natural to the first man and mortality is natural to us. He was created immortal; we are born subject to death.
Latin
XVI. Praeterea naturale significare potest quod cuique inest a nativitate, sive sit naturae bonum atque conveniens, & naturali appetitui consentaneum, sive non. Et ita quoque fatetur primo homini immortalitatem, mortalitatem vero nobis naturalem esse. Ille enim immortalis conditus fuit, nos autem nascimur morti obnoxii.