One of the many golden nuggets of wisdom in Mere Christianity is Lewis’ description of the three parts of morality.
Many people have tried to boil down morality to the slogan, “If it doesn’t harm anybody else it’s fine.” It is not difficult, however, to show that this falls short as a sufficient foundation for ethical decision making. There are at least two significant problems we can note with this approach.
First, it is necessary to carefully define what “harm” means. I have observed that many of those who use this, or similar slogans, are not big on offering careful definitions. As it is, harm is far too ambiguous. By harm do we mean only physical harm? Ought we to also include emotional harm? What about pecuniary harm? Are there no times in which causing physical harm to another person is appropriate? What about in the case of confronting someone during a home invasion? What if you are a soldier in a just war? What if you harm someone’s feelings by telling them the truth? What if you harm someone’s livelihood by offering a better product than the one they are selling? Many more questions like these could be posed but these are sufficient to demonstrate that more clarity is needed when we say “do no harm”.
Second, this ethical slogan fails because it assumes the radical autonomy of the individual which is simply false. The slogan focuses on the self and it seeks for permission to do anything one wants if only it can avoid “harming” others. But this does not at all take into account the fact that self-harm can also be harmful to others. We do not live in a vacuum and our personal decisions and actions always affect others. I might think that it’s fine to take narcotics as long as I am not giving them to my neighbor, but I still live next to his neighbor! Drug abuse makes people do things they never thought they would. You still have a job where other people depend upon you. You may have a spouse or children who need you to think clearly and behave responsibly. Your actions, even if aimed at self, invariably will affect those around you. Society is made by individuals functioning collectively. When one member suffers, society suffers.
C. S. Lewis offers the following analogy:
There are two ways in which the human machine goes wrong. One is when human individuals drift apart from one another, or else collide with one another and do one another damage, by cheating or bullying. The other is when things go wrong inside the individual—when the different parts of him (his different faculties and desires and so on) either drift apart or interfere with one another. You can get the idea plain if you think of us as a fleet of ships sailing in formation. The voyage will be a success only, in the first place, if the ships do not collide and get in one another’s way; and, secondly, if each ship is seaworthy and has her engines in good order. As a matter of fact, you cannot have either of these two things without the other. If the ships keep on having collisions they will not remain seaworthy very long. On the other hand, if their steering gears are out of order they will not be able to avoid collisions.
Clearly, then, it is not enough to simply tell ourselves “as long as it doesn’t harm someone else it’s fine.” The truth is, self harm inevitably brings harm to others too. A man hopelessly addicted to pornography is not going to be able to treat women with the respect they deserve. He may reason, “I’m not actually harming anyone by looking at my computer” but he is certainly harming his soul and that darkened soul will interact with others for the worse. He is also contributing to an industry that preys on young women and strips them of their dignity as image bearers (not to mention pornography’s link to sex trafficking). The truth is, our ability to “not harm” our neighbor is impaired the more we harm ourselves. As we descend into habits which destroy us inwardly we become a person who does harm to those in our proximity. It’s not ultimately possible to keep our mess contained, it spills over onto others. This is just what the ancients and medievalists were talking about when they discussed the virtues and vices. Both of these alike are habits and, although they may be developed in private, they will most certainly be displayed in public for good or ill. So we must actually refrain from evil in our own lives also and not just refrain from harming our neighbor.
But there is another aspect of morality we have not yet discussed, namely, morality toward our Creator. Even if you were the last person on earth your moral obligations would not be absolved. You would still not be alone nor would you belong only to yourself. You and I belong to God and we owe him a life of obedience to his good commandments. A person marooned on an island would still be responsible to God for the thoughts of his heart and he still ought to worship the Lord as is his due. So simply refraining from harming others misses the mark on this front as well.
Finally, I would say that there is something else fundamentally wrong with the idea of “do no harm” as a foundation for ethics. Our moral duties are not best stated in the negative but, rather, in the positive. That is to say, we have positive moral duties to God, neighbor, and self. It is not merely that we ought to refrain from harm, rather, we ought to positively give ourselves to good works of obedience to God, to works of kindness to our neighbors, and to developing virtue in our personal lives.
It has been pointed out by some that Jesus is not the first moral teacher to tell us, “Don’t do to others what you don’t want them to do to you.” But, in reality, Jesus never actually said this at all. Jesus teaches us, “So whatever you wish that others would do to you, do also to them, for this is the Law and the Prophets.” (Matthew 7:12) Jesus actually takes what may very well have been an older proverb, well known to his hearers, and turns it on its head. Just as Jesus taught us to “turn the other cheek” and to “love your enemies and pray for those who persecute you” so Jesus tells us that just refraining from evil is not enough. We are to actively do good to our neighbor without concern for whether they are doing good for us. We are to love God, not just avoid breaking his law. We are to grow in righteousness, even when it seems like we can keep our vices secret. God’s moral law is not about refraining, its about acting in love and faith toward God, neighbor, and self.