Lying and Common Sense

Is lying always wrong? A consequentialist argues that Kant’s prohibition against lying must at times be set aside when the consequences of the truth are too dire.

Is lying always wrong? A consequentialist argues that Kant’s prohibition against lying must at times be set aside when the consequences of the truth are too dire.

It’s common sense that lying is wrong, and, because of that, we shouldn’t do it. But common sense only allows us to skim the surface. That’s all we need in many cases. Take surfing, for example: the surface is just where we want to be, and woe betide anyone who plumbs the depth. On the other hand, to continue with the aquatic metaphors, consider buying a sailboat. We certainly want to examine the hull to the waterline, but we would be wise to look below the surface. So, is examining the morality of lying more like surfing or buying a sailboat? I think it’s more like the latter, and that’s the strategy I shall follow here.

But enough of the nautical metaphors, already. It’s time to get down to serious business. There are a number of things about lying that common sense is inadequate to tell us. First and foremost is the question, what makes lying morally wrong? Then, is it always wrong, no matter what the circumstances? Should we never tell a lie, no matter what? Are there some lies which are more wrong than others? Why would that be so? If some lies are more wrong than others, do lies fall on a scale that measures actions in general, such that this lie is morally preferable to that theft, which in turn is morally preferable to this second lie, which in turn … and so on? Are there things which are not lies, but which are wrong for the same reasons?

Let’s begin with the most important question. What makes lying morally wrong?1 Immanuel Kant provides us with an insightful answer. To see the strength of it, we might ask whether we can lie to an animal such as a dog. Of course we can’t; at least not in the same way we lie to language users. We can, for example, deliver false information to a dog when we feign throwing a ball, but this isn’t lying as I define it at the close of this paragraph. This leads to the last question I posed in the previous paragraph, but I’m going to take these questions in order, so I shall shunt it aside for the moment. The present point is that we can lie only to those who use language at a level sophisticated enough to require rationality. So, that lets in us humans, but leaves out dogs. Kant’s insight is that it is the interference with our rational processes that makes lying wrong. As rational creatures (which means that we are capable of rationality, not that we always live up to our billing) we need accurate beliefs upon which to deliberate. But lying just is the intentional dissemination of inaccurate information,2 so no rational person could consistently accede to being lied to. Ever.3

There are a number of things about lying that common sense is inadequate to tell us.

This gives us a very strong reason to conclude that lying is always wrong, which is Kant’s answer to the second question from the list in the second paragraph.4 That is, lying is always wrong. And Kant, along with most people, held that the answer to the next question on my list follows automatically as well. It’s just common sense that if lying is always wrong, then we should never do it.

But let’s not be too hasty here. This latter conclusion follows only if we understand right and wrong in a certain way, which is the way Kant understood it. He thought of right and wrong as a dichotomy, working in the way that a light switch works. If the light switch is in the on position, then it’s not in the off position, and vice versa. There are no degrees of offness; there is just off. And the same for on. But does rightness/wrongness work this way? Surely not. There are degrees of rightness and wrongness, both within the category of lying and between lying and other actions. More on the latter in a moment, but for now let’s stick to lying. Think of, on the one hand, the lies that New York Congressman George Santos has told to get people to buy into his various schemes, from buying yachts and stocks, to electing him to Congress. On the other, think of the current Prime Minister’s father’s claim that he may have once said “fuddle duddle” in Parliament.5 It’s not because of any patriotism or commitment to liberalism (neither upper- nor lower-case L) that we conclude that the former is morally worse than the latter.

Once we accept that lies fall on a scale from morally trivial to evil, it is no stretch to agree that all actions fall on this one scale, against which Trudeau should have measured the immorality of his lie against the harm to the nation of his not being in parliament for the day because the Speaker would have been dutybound to kick him out for unparliamentary speech. That Trudeau measured the latter harm as worse than the former is a testament to the size of his ego, which is again something to be measured on that scale. And, of course, what holds at the trivial end of the scale holds for measurements and more significant levels, as we see in the case, often presented to first-year moral philosophy students, of the Gestapo arriving on your doorstep, questioning you directly whether there are Jews in your attic.6 It is presented with three intentions, first, of getting them to think about whether moral situations involve trade-offs between competing values, and second, where lying falls among those trade-offs. And a third, some of us align ourselves with Kant in thinking of the prohibition against lying and the duty to preserve human life as absolutes, but they couldn’t both be if it is possible for them to be in conflict.

Fortunately, very few of us face choices as stark as this one, involving life and death. But we all do have to make choices involving the ranking of values, even if we can occasionally avoid having to choose between them by finding a clever solution which allows us to have both. Inevitably we will have to pull out our scale to rank the competing values involved, in order to decide which to jettison in order to preserve other ones. What we need now is a moral theory to explain how such a scale should work. The theory I argue for is Classical Utilitarianism, which all moral philosophers grant is the best theory for explaining the moral scale. Those who criticise Utilitarianism do so by arguing that there are things of moral significance which cannot be weighed on such a scale. However, these critics are generally left staring at their feet and mumbling when asked how we should decide what to do if we can’t decide that one action is better or worse than another. To maintain that there are no answers to (some) moral dilemmas is just to open the door to some brute stepping in to settle things. So, I maintain, Classical Utilitarianism is our best option. It can be stated by citing the one principle to guide our actions, the Principle of Utility:

Of the actions open to you at a time (including doing nothing), choose the one that produces the most utility.

This prescription contains three ideas. The first is denominated by the word ‘produces’. It is emphasizing that what we are measuring on our scale is not actions but consequences. The same lie told in one situation will produce one set of consequences, but told in another a totally different set. “I was home all night” may be a relatively harmless lie when told by a teenager to his helicopter parent, but may be very different when told by a murderer using it as an alibi. Or, to see another reason to pay attention to consequences rather than actions, we might turn to the last question on the list I gave in the second paragraph, whether there are other deceptions which are not strictly lies but which are just as bad. There are a range of cases, from the ‘Lie of the Face’ one puts on when having to sample a dish of a child who is just learning to cook, to getting up from the table, signaling you are finished negotiations when you are just trying to force your adversary to sweeten his counteroffer. These bodily movements can have the same consequences as a verbal falsehood, and so are just as right or wrong – depending on the consequences they produce. Finally, it is important to note that account of what makes lying wrong that I presented above from Kant is really singling out of the consequence of lying: it interferes with our capacity to evaluate what is going on. And there are further consequences when we act on these faulty perceptions that make the lie even worse: I lie to you about whether the gun is loaded and the safety is on, so you pick it up, and … 

‘Utility’ must be defined, and I shall get to that in a moment; but first the ‘most’ part. That word needs no definition, but what it signifies needs emphasis. When it comes to right and wrong, more of the former is aways better than less, and less of the latter is always better than more. Same thing for goodness and badness. So, an elegant way of thinking about morality is what the Principle of Utility is based on, the idea that right and wrong actions are determined by the amount of goodness or badness they bring about. The more goodness an action produces, the more right it is, and the more badness, the less right. Utility is simply another term for goodness/badness. So, what is utility? Since I have already defended the answer to this question in these pages,7 I will just rely on a commonsense answer here. The one thing that we can be sure that humans will want more rather than less of is positive human experience. Here are some examples of what I mean by this: contemplating a great work of art, solving a complex mathematical problem, finishing a 1000-piece jigsaw puzzle, or having a hot bath after chopping a lot of wood. And some examples of experiences everyone would want less of rather than more: finding out that you didn’t get the job you’d hoped to get, the smell when a sewer line has been exposed, and the feeling one has when first learning that a favorite relative has died.

The Principle of Utility is stating that our aim in doing anything – lying is just one case — should always be to bring about the maximum number possible of positive experiences and the minimum number possible of negative ones. And not just for ourselves or our loved ones, either. And not just for humans, but for all the conscious beings capable of experiencing them. This includes whales, beaver, chickens, and so on. Not that the latter will be directly affected by a lie; but they certainly can be indirectly affected, as will be the case when humans act on the basis of a lie (“They won’t feel anything …”). For Utilitarians, all the consequences that affect conscious beings matter. This emphasis on consequences underscores our commonsense view that lying is almost always wrong. But on the other hand, it shows that on rare occasions it will actually be our duty to lie, to prevent dire consequences that are worse than those that arise from lying. And if that isn’t part of common sense, it should be.


  1. Notice the important qualifier morally. A lie may not be strategically wrong, as it may be your only route out of hot water, nor legally wrong, since there are no laws against lying per se. The state rightly views a law against lying as being impossible to enforce, and attempts to enforce such a law as too intrusive in our private lives. Lying in specific, controlled situations, such as laws against perjury or lying in a contract, are a different matter. When I use ‘wrong’ from now on, I shall be meaning ‘morally wrong’ unless I specify otherwise.
  2. Why not false information? Because a falsehood is just the most egregious case of the kind of misinformation which stymies our rational processes. Misleading information, such as when an employer writes a letter of recommendation for an employee that she considers herself well rid of, stating that he “leaves a hole in the organisation that won’t be easily filled”, can interfere with the rational decision-making of those considering hiring him just as much as a straightforward falsehood. But more on this when we get to the questions about whether some lies can be morally worse than others, and whether there can be things which are similar to lies and just as harmful.
  3. This claim can be questioned: look at the numbers of people who, through self deception, willingly invite doctors, politicians, advertisers, and the like to make them feel temporarily comforted by lying to them. Kant’s response is that this would be a temporary lapse in their rationality; so, strictly speaking, they weren’t rational when they made the request. But we shouldn’t allow this verbal manoeuvre. The important point is that even when someone tacitly agrees to be lied to in these extreme cases, they won’t accept people to lying to them indiscriminately.
  4. The reason, in a nutshell, is this. Moral wrongness consists in the violation of his Categorical Imperative, the Principle of Reason which governs that part of rationality we use to determine what we ought to do. It violates the second formulation (scholars identify five) of the Categorical Imperative, “So act as to treat humanity, whether in your own person or in that of another, in every case at the same time as an end, never as a means only” (Thomas K. Abbott tr., Lara Dents, ed., Groundwork for the Metaphysics of Morals, Peterborough, Ontario, Broadview Press, 2005. Kant’s original publication was 1785). This needs a bit of translation. The idea is this: Every human (person) has ends – goals, aspirations, plans and such. When you give them a false promise (lie to them about your intention to keep it) you are treating them as a means to your ends, in a way that frustrates their pursuit of their own ends. And that is just what this formulation of the Categorical Imperative is prohibiting.
  5. Someone determined to preserve the idea that no one should ever lie, no matter what, yet unwilling to condemn Pierre Trudeau for his ‘fuddling’ with the truth, may attempt to argue that what Trudeau said wasn’t strictly speaking a lie, since it wasn’t so much done with the intention to deceive us as with the intention of asking us to pretend to be deceived, so we might forgive him for transgressing a parliamentary rule deemed to be absolute. Fair enough; but it is easy to come up with other examples of clear lies which we would hold to be less wrong than George Santos’s porkies. For an interesting discussion of this effort to characterise lies as something else in order to preserve the absolute prohibition on lying, see Chapter III of Sissela Bok’s essential work on the subject, Lying: Moral Choice in Public and Private Life (New York, Vintage Books, 1978).
  6. Kant considered just such a case – that of a murderer chasing your friend, who stops to inquire of you whether the friend has taken refuge in your house. Kant says that one ought not to lie even in this situation. (“On a Supposed Right to Lie Because of Philanthropic Concerns”, in an appendix to James W. Ellington tr., Grounding of the Metaphysics of Morals, Indianapolis, Hackett Publishing, 1993). Kant’s original essay was published in 1799 in response to an essay published in 1797 in a French journal by Benjamin Constant, “On Political Relations”. Kant not only sticks to his guns about lying, he refuses to take a way out offered to him by Constant which would allow him to hold an absolute prohibition against lying. Constant maintains that our duty to tell someone the truth holds only to. those who have a right to the truth, and a murderer has no such right. So it wouldn’t really be abrogating the rule against lying in this case. But Kant will have none of this: he maintains that our duty to tell the truth isn’t a duty to individuals, it’s a duty to tell the truth no matter what. So it would be violating the prohibition against lying, and too bad for the friend.
  7. “Environmentalism, Utilitarianism and Humanism: The Three Amigos”, Humanist Perspectives, Issue 224 (Spring 2023).