Adrian brought up an interesting question earlier this week in an email correspondence. Since the only people able to read our blog are the people involved in the email correspondence, I thought it would be a good idea to make the discussion available on the blog. (There are important principles and concepts within Thomism that are related to this discussion. As such, it is a fruitful opportunity to learn.)
If anyone has replied and their reply is not part of the discussion posted below, please add your reply in the comments. If you have not replied, please enter the discussion by making use of the comments here on the blog.
Adrian's Original Email:
Guys,
The following is a sentence in Humanae Vitae II. 14.:
"Though it is true that sometimes it is lawful to tolerate a lesser moral evil in order to avoid a greater evil or in order to promote a greater good," it is never lawful, even for the gravest reasons, to do evil that good may come of it (18)—in other words, to intend directly something which of its very nature contradicts the moral order, and which must therefore be judged unworthy of man, even though the intention is to protect or promote the welfare of an individual, of a family or of society in general."
I went to a men's study at Wisdom tonight. I asked what an example was for the first part of the sentence, i.e. "that sometimes it is lawful to tolerate a lesser moral evil in order to avoid a greater evil or in order to promote a greater good". Deacon Tim (can't remember the last name) responded with the scenario of lying to Nazis in order to save the hidden Jews' lives. Ironically, that very example contradicts the last part of the sentence, i.e. "even though the intention is to protect or promote the welfare of an individual, of a family or of society in general."
Can anyone think of an applicable example?
Adrian
Joe
I think that's basically the principle of double effect. I can commit an act that is of itself not inherently evil, even if it will have an evil result, so long as the good object outweighs the evil effect. So, for example, in and of itself speaking a misleading truth is not an intrinsic evil, so provided that the object of doing so is good (for instance to save a life), then one can justify the act even though it has an evil effect.
Kyle
I'm not sure if the principle of double effect applies here. I could be mistaken, but I thought the principle of double effect applies to acts which are not morally evil in themselves but rather have unintended evil outcomes (for example, removing a malignant tumor from the uterus of a pregnant woman that results in the unintended killing of the child). The principle of double effect, as Joe mentioned, applies only when the intention is directed towards a good act that outweighs an evil effect.
In Humanae Vitae, we see a related but different scenario. First, we see mention of scenarios which a lesser moral evil is tolerated in order to avoid a greater moral evil, and in so doing, promoting a greater good. As Adrian originally highlighted, it is difficult to think of a concrete example here. The principle of double effect, however, doesn't seem applicable because we don't have a greater good mediating between a lesser moral evil and a greater moral evil. The key term is "moral ". In the principle of double effect, we don't see an act which is itself a moral evil only an unintended evil effect. The act in question, then, that falls under the principle of double effect cannot be said to be a moral evil. In sum, the first part of the statement from Humanae Vitae makes mention of acts that are morally evil in character. Acts that fall under the principle of double effect are found to not be morally evil by virtue of the principle itself. Therefore, the moral character of acts in the first part of the statement from Humanae Vitae do not seem to be those that fall under the principle of double effect.
In thinking about examples that would apply, I think the key term is "tolerate". I will try to demonstrate this sense of tolerate with an example from Pope Benedict followed by a more general scenario. The only concrete example I can think of that reflects the first part of the statement from Humanae Vitae is Pope Benedict's recent (seemingly) controversial statement about condom use with certain individuals from Africa. The condom use is still a moral evil. However, the pope notes that it is a lesser moral evil than spreading disease. This does not make the act moral, but the pope notes the movement towards a greater good.
Practical examples we can think about ought to reflect the sense of toleration in the statement. Often, people trying to break a habit of mortal sin may engage, out of desperation, in lesser moral evils. For example, someone fighting an addiction to cigarettes may find themselves committing lesser moral evils such as choosing to engage in compulsive eating and outbursts of anger to deal with the effects of breaking the addiction. While there are better ways to handle this (and often the moral character of these acts are certainly mitigated by the state of the person), the Church recognizes their movement towards a greater good. Toleration comes into play by recognizing this movement. The greater good doesn't nullify the moral character of the lesser evils (as with the case in the principle of double effect). The greater good serves to be a lens into the trajectory of the individual's intentions. Tolerate, then, should be interpreted as compassion not condoning.

The second part of the statement from Humanae Vitae should be seen in this same light. Toleration seems applicable in the first part for individuals with poorly formed consciences. The trajectory towards the greater good is the formation of a conscience. Again, tolerate and condone are not synonymous here. The Church makes this abundantly clear in the second part of the selected statement from Humanae Vitae. While we can understand the grip of consequentialism in cases like the Nazis at the door, we never see it as a morally good act to commit a lesser evil to prevent a greater evil. The Holy Church firmly declares that the morality of an act is never determined by consequences but by its very nature. The person who lies to the Nazis cannot be said to be demonstrating the virtue of a saint. It would be just as absurd to say that the characters in the Boondock Saints are committing morally good acts because they are preventing more crime and murder. Unfortunately, many people would think otherwise. (Hence, I think, many people's attraction to that movie: it turns morality on its head and that makes people feel good about turning morality on its head in their own life; granted, this is certainly not the case for everyone who enjoys that movie. Some people just enjoy the acting of William Defoe.) I think it is incredibly important to propagate the Church's teaching found here in Humana Vitae--not out of a lack of compassion for individuals who genuinely struggle to avoid the grips of consequentialism, but as a witness to the person of Christ who would rather die than have us slaves to the most venial of sins.