In a recent Public Discourse article, Matthew O’Brien observes that in the seminar room and in the public square, theists often avoid invoking God and His commandments in making moral arguments lest non-believers dismiss them as unreasoning fideists. But O’Brien thinks that this is a mistake. He argues that although we can show, without invoking God and His commandments, that some actions are intrinsically evil (e.g., intentionally killing the innocent), nevertheless we cannot show in this way that we ought always to avoid such actions. For, O’Brien says, without relying on divine legislation, it is possible to think that although intrinsically evil actions ought usually to be avoided, nevertheless they ought sometimes to be done—namely, in the rare cases when the consequences of doing them are on balance very good. In other words, we need to rely on God’s commandments to know that we may not do evil that good may come of it.
O’Brien is clearly right that theists such as Robert P. George and Christopher Tollefsen eschew theological premises in moral argument in order to win a hearing among non-believers. In so doing, they follow a tradition going back at least to St. Paul at the Areopagus. Not all theists follow this line, however. Tim Tebow, for instance, explains his moral views in expressly, even flamboyantly, Christian terms.
The difference here is not merely one of temperament or rhetorical strategy or intellectual sophistication; it goes much deeper, even to the very foundations of morality. For some people—including many Protestant Christians under the influence of Martin Luther—believe in what might be called a divine command theory of morality. On this theory, it is not that some actions are right and others are wrong, with God commanding us to do the right ones and avoid the wrong ones, but that right actions are right precisely because God has commanded them and wrong actions are wrong precisely because God has forbidden them. God’s commanding or forbidding makes actions right or wrong. On a theory like this, it is obviously impossible to argue that a particular action is wrong without invoking the divine command, for there is nothing else to which to appeal. No wonder, then, that people who accept a divine command theory are quick to invoke God and His commands in moral argument.
But divine command theory is in many ways unlovely. Suppose God had commanded us to slaughter our firstborn sons and feast on their roasted flesh marinated au jus; would this be morally permissible? On pain of inconsistency, the divine command theorist must say that it would be not only permissible but obligatory. If his good sense takes over and he says that God could not or would not command such a thing, then there must be some reason for this, and that reason almost certainly is a reason why such actions are morally wrong. But if there are reasons independent of the divine command why certain actions are morally wrong, then divine command theory collapses. Thus, philosophers going back to Plato in the Euthyphro have generally rejected divine command theory.
Now, even without divine command theory, most moral philosophers prior to the twentieth century, theists and non-theists alike, have held that there are some actions that ought always to be avoided, regardless of the consequences or the circumstances. Aristotle and Kant, who agree on very little else, agree on this. I suppose O’Brien could say that the accounts that these philosophers offer all fail and only an appeal to divine legislation will suffice, and, to be sure, the idea that only theistic ethics succeed is trendy nowadays, as in the work of Michael Perry and Nicholas Wolterstorff. I, however, am not convinced.
Consider O’Brien’s treatment of Aristotle on this issue. Noting that Aristotle thought that adultery, theft, and murder are always wrong, O’Brien says that Aristotle does not try “to demonstrate the truth of such absolute prohibitions by appealing to some more basic set of moral reasons.” Rather, “for Aristotle … the grounds for absolute prohibitions bottom out in the perception of actions as base and shameless.”
This makes Aristotle sound rather like G. E. Moore, and O’Brien quite aptly describes the view he attributes to Aristotle as “intuitionism.” But as far as I can see, this account bears no relation to what Aristotle actually says. In the relevant passage in the Nicomachean Ethics (1107a8–1107a27), Aristotle makes no mention of perceiving the baseness of these actions but rather produces a substantial argument about why such actions are wrong. Appealing to his doctrine that virtuous actions lie in a mean between opposing vices, Aristotle says that actions such as adultery, theft, and murder connote vice (i.e., either excess or defect), and so to say that these actions could be right (i.e., lie in the virtuous mean) would be to say that there could be a mean of excess or a mean of defect, which he evidently regards as a contradiction in terms. Whether this argument for absolute prohibitions on such actions succeeds is, of course, open to debate, but Aristotle clearly intended it as an argument, not an appeal to intuition, and Thomas Aquinas accepts and repeats the argument in his commentary on the passage.
Aristotle’s doctrine of the mean is an unhelpful metaphor, but, in the larger context of Aristotle’s moral theory, it can be interpreted in a straightforward enough way. Aristotle is a eudaemonist, meaning that he thinks that man has a natural final end and that actions are right or wrong depending upon whether they are ordered as means to that end. Now, for any given end, an agent’s action may fail to advance that end for any number of reasons, e.g., because the agent does the wrong thing, or acts at the wrong time or at the wrong place, or performs the action in the wrong way, etc. In order to advance the end, the agent’s action must simultaneously be the right kind of action, done at the right time, in the right place, in the right way, etc. When Aristotle says that the virtuous action lies in a mean relative to the agent, he means primarily that a virtuous action must be right in all respects in the totality of the actual circumstances if it is to advance the agent’s natural final end.
In a theory such as this, it is not hard to see how some actions will be absolutely prohibited. For, given any end whatsoever, if the end be sufficiently specified, we can identify actions that will never advance it, regardless of the circumstances. For instance, if the end is delivering medical services in a hospital, embezzling the hospital’s funds for personal consumption will never advance that end. There is nothing mysterious about such claims; they are ultimately causal claims that certain causes (i.e., certain actions) cannot produce certain effects (i.e., the given end). Thus, if the final natural end for man is sufficiently specified, there will be some actions that cannot be means to that end, and these actions are thus always wrong and so absolutely prohibited. That is how Aristotle, at least as interpreted by Aquinas, thought about the matter. And if this is right, we can indeed know that some actions are absolutely prohibited without relying on the divine command.
This is good news, for if we had to rely on the divine command even for the limited purpose of explaining why some actions are not merely usually wrong but always wrong, we would involve ourselves in all the unloveliness of divine command theory. Why, after all, does God prohibit certain actions absolutely, even if on balance their consequences are so good? Is it just because He hates consequentialism the way He hated Esau? This would be a hard saying. In my view, if God prohibits some actions absolutely, regardless of the circumstances, He does so not arbitrarily but for a very good reason—for instance, because such actions cannot be ordered to the final end for man. And if this is the case, then the absolute prohibition can be justified without reference to the divine command after all.
That said, I think O’Brien is on to something important here. For, in our fallen state, when we are faced with an action that, although absolutely prohibited, has consequences that seem to us to be on balance very good, we are sorely tempted to ignore the absolute prohibition or to rationalize some exception to it and proceed with the action. Recall that Tollefsen, to whom O’Brien was responding, was arguing that the nuclear bombing of Hiroshima and Nagasaki was morally wrong because it involved intentionally killing the innocent, even though it likely saved tens of thousands of American lives that would have been lost in an invasion of the Japanese home islands. I agree with Tollefsen on this point, but I do not judge President Truman harshly, for I recognize how easily even a good man might make the decision he did.
Some actions are incapable of being ordered to our final end, and these actions are always and everywhere wrong. God absolutely prohibits such actions, but the divine legislation functions not to ground the absolute prohibition but to enforce it.