Lactantius

“ But if virtue, which despises all earthly goods, most wisely endures all evils, and endures death itself in the discharge of duty, cannot be without a reward, what remains but that immortality alone is its reward? For if a happy life falls to the lot of man, as the philosophers will have it, and in this point alone they do not disagree, therefore also immortality falls to him. ”

“ But if natural philosophy is superfluous, and this of logic, and the philosophers have erred in moral philosophy, which alone is necessary, because they have been unable in any way to find out the chief good; therefore all philosophy is found to be empty and useless, which was unable to comprehend the nature of man, or to fulfil its duty and office. ”