The Euthyphro dilemma is found in Plato's Euthyphro dialogue, in which Socrates asks the question, "Is the pious loved by the gods because it is pious, or is it pious because it is loved by the gods?" In layman's terms this would be, "Is that which is good commanded by God because it's good, or is it good because God commands it?"
Christians like to say that since God is omnibenevolent, whatever he commands is good by definition. They further state that things are good simply because God commands them. This is obviously circular reasoning.
The Euthyphro dilemma can be seen as analogous to the question "Who created God?" In this case, we are told that morality is meaningless unless it is derived from an external source, such as God. Therefore, the counter-question is, "Who made God moral?" Obviously under most descriptions of God, the answer is "nobody", which raises the very reasonable question of whether a god's moral decisions could be considered objective rather than arbitrary.
To put it another way, if things are neither right nor wrong independently of God's will, then God cannot choose one thing over another because it is right. Thus, if he does choose one over another, his choice must necessarily be arbitrary, and a being whose decisions are arbitrary is not one worthy of worship.
Does God freely decide what is good? There are two possible responses, and neither one really resolves the dilemma.
The first answer is: Yes, God is free to decide what is good, and it is good by virtue of his decree. If this is the case, then God has no higher standard to answer to, and therefore his will may be seen as genuinely arbitrary. Although God once decreed that murder and theft are morally wrong, he might have declared the opposite just as easily, so then murder and theft would be right.
The second answer is: No, God cannot change what is right and wrong. Killing and stealing are inherently bad, so God, being inherently good, cannot command them. Yet if right and wrong are inherent to the action, regardless of God's decree, then God has nothing to do with the process. God doesn't set moral standards; he follows them, and is therefore irrelevant to morality (except to the extent that he could tell us things which we could not figure out for ourselves.)
In summary, either such acts as murder are not inherently wrong (because God can set the rules whichever way he wants to) or God is powerless over the meaning of morality.
The effective use of the argument is as follows:
(1a). The Good is willed by God because it is the Good.
(1b). The Good is the Good because it is willed by God.
2. If (1a) is true, then the Good is independent of God’s will.
3. If (2) is true, then God did not create the Good, and is not Creator.
4. If (1b) is true, then the Good is contingent and subjective (to God’s will).
5. If (4) is true, then there is no objective standard of morality, and the absolute of value-selection is false.
6. God does not exist. (from 1, 3 and 5)
Much atheist literature has borrowed from the Euthyphro dilemma, even when not referring to it by name. For instance, Bertrand Russell wrote:
"The point I am concerned with is that, if you are quite sure there is a difference between right and wrong, then you are then in this situation: is that difference due to God's fiat or is it not? If it is due to God's fiat, then for God himself there is no difference between right and wrong, and it is no longer a significant statement to say that God is good."
There are several responses possible against the Euthyphro dilemma, but the sharpest criticism it falls under is that it is a false dilemma (i.e., commits the Bifurcation fallacy by presenting only two alternatives when there are actually more than two). The two cases presented are that (i) God commands something because it is good, and that (ii) something is good because God commands it. In the first instance, moral order is grounded outside God; in the second instance, moral order is grounded in God's arbitrary fiat.
The Bifurcation fallacy is proved by the existence of a third alternative, which it fails to present or account for; namely, (iii) that moral order is grounded in the very nature of God and expressed prescriptively in his commands. In this case God's commands are not arbitrary; they are, rather, an expression consistent with his essential nature. Under this view, "God is good" is not a moral valuation (God has goodness) but an ontological statement (God is goodness); as a logical consequence, good is that which conforms to the nature and will of God, while evil is a privative term or that which does not conform to the nature and will of God.
This supplies the reason behind why "an all-loving God would never command evil." Under the Euthyphro bifurcation, the Christian theist has no reason to believe that God would never command evil on the one horn, or that God will not change his mind about what is evil on the other. However, under the third alternative the Christian theist does have good reason for his belief, that God commanding evil would amount to a logical contradiction: God wills what he does not will, an empty nonsense statement.
God would never command immoral acts
Firstly, God does command rape and murder several times in the Old Testament. For example, in Numbers 31:1-54 God commands Moses and his army to "Kill every male among the little ones, and kill every woman that hath known man by lying with him. But all the women children, that have not known a man by lying with him, keep alive for yourselves." The army comes back with 32,000 virgins after doing God's will.
The Qur'an, chapter 4 (An-Nisa), verse 34: “ Men are the maintainers of women because Allah has made some of them to excel others and because they spend out of their property; the good women are therefore obedient, guarding the unseen as Allah has guarded; and (as to) those on whose part you fear desertion, admonish them, and leave them alone in the sleeping-places and beat them; then if they obey you, do not seek a way against them; surely Allah is High, Great.
Secondly, saying that God would never command evil in itself shows that God gets his morals from an outside source. If God would never command rape and murder because they're evil then where did he get the determination that they were evil?
This counter-apologetic contains certain risks, however, which a canny apologist may exploit. The theist may contend, sincerely or otherwise, that yes, because God commanded all of the ostensibly immoral acts contained within both Old and New Testament, they are therefore good. The theist can then shift the burden of proof to the counterapologist and demand that he or she justify why such acts are objectively immoral, opening the door to endless picayune objections, diversions, and moving of the goalposts.
The claim that God would not command evil because it goes against God's nature does not actually change the problem, but only reorganizes it. The question might then be reasonably asked, "Where does God's nature come from?" Did God create it himself? If so then God's whims are still behind what he considers right and wrong, and the dilemma still applies. If, on the other hand, God did not create his own nature, then either someone else created it (in which case the dilemma applies to the creator of God's nature) or the morality contained in God's nature is inherent in some way (in which case God is not truly the author of right and wrong). Michael Martin has argued that theistic objections to the dilemma solve nothing, because it can easily be reformulated in terms of God's character: "Is God's character the way it is because it is good or is God's character good simply because it is God's character?" The structure of this modified dilemma is exactly the same as before, and it appears to be if anything harder to escape.
If we identify the ultimate standard for goodness with God's nature, then it seems we are identifying it with certain of God's properties (e.g., being loving, being just). If so, then the dilemma resurfaces: is God good because he has those properties, or are those properties good because God has them?
Can you be good without God?
The issue of secular morality is a complex topic and is further explored in the related article.
- Full text of the Euthyphro dialogue by Plato