Sextus Empiricus was a Greek Pyrrhonist, a school of philosophical skepticism founded by Pyrrho in the fourth century BC. Sextus promoted a form of philosophical inquiry called the “skeptic way,” which involves counterposing two or more credible but seemingly inconsistent assertions in order to demonstrate the limits of logic. The excerpt below, taken from the chapter titled “God” in Outlines of Pyrrhonism, is the earliest known written formulation of the problem of evil as a “trilemma”—a three-part problem in which the existence of evil is juxtaposed against the divine attributes of omnipotence and omnibenevolence.
“God”
Anyone who says that god exists either says that god takes care of the things in the cosmos or that he does not, and, if he does take care, that it is either of all things or of some. Now if he takes care of everything, there would be no particular evil thing and no evil in general in the cosmos; but the Dogmatists say that everything is full of evil; therefore god shall not be said to take care of everything. On the other hand, if he takes care of only some things, why does he take care of these and not of those? For either he wishes but is not able, or he is able but does not wish, or he neither wishes nor is able. If he both wished and was able, he would have taken care of everything; but, for the reasons stated above, he does not take care of everything; therefore, it is not the case that he both wishes and is able to take care of everything. But if he wishes and is not able, he is weaker than the cause on account of which he is not able to take of things of which he does not take care; but it is contrary to the concept of god that he should be weaker than anything. Again, if he is able to take care of everything but he does not wish to do so, he will be considered malevolent, and if he neither wishes nor is able, he is both malevolent and weak; but to say that about god is impious. Therefore, god does not take care of the things in the cosmos.
Further, if god does not take care of anything and there is no work or product of his, nobody will be able to say from whence he apprehends that god exists, if indeed god neither appears of himself nor is apprehended through his products. And thus, whether god exists is not apprehensible. From these considerations we conclude that most likely those who firmly maintain that god exists will be forced into impiety; for if they say that he takes care of everything, they will be saying that god is the cause of evils, while if they say that he takes care of some things only or even of nothing, they will be forced to say that he is neither malevolent or weak, and manifestly these are impious conclusions.
Sextus Empiricus, Outlines of Pyrrhonism, III.3; in The Skeptic Way: Sextus Empiricus’s Outlines of Pyrrhonism, trans. Benson Mates (New York: Oxford University Press, 1996), 173-5.