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13: Telling Lies

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  • I’m not upset that you lied to me; I’m upset that from now on I can’t believe you.

    Friedrich Nietzsche

    1. Introduction

    What is it to tell a lie? Is it always wrong to tell lies? Is it sometimes acceptable to lie, and if so, what are the conditions that make it OK? Humans have dealt with these types of questions, regarding lies and truth, ever since they began to interact with one another. Truth and trust are key to the working of our society, in fact people who are caught in a lie are sanctioned, blamed and punished. We have many examples of politicians being brought down by lies; Nixon and the ensuing Watergate is a good one (although see the final section regarding Politicians). Children are told “not to lie”, religious leaders and religious texts condemn lying, relationship guidance talks about the importance of not lying to your partner etc. We will start to consider some of these questions and apply some of the thinking thus far discussed in the book to lying.

    2. What Is It to Lie?

    Let’s consider some examples; when you read them you should ask yourself whether there is a lie involved.

    1. A friend asks you where you went on holiday last year. You say “Cambridge”, which they understand to be Cambridge, UK, but you really mean Cambridge, Massachusetts.
    2. You are teaching chemistry to primary school children and you hold up a football and say “Atoms are just like this…”
    3. You are having a really bad day: your partner has split up with you, you have lost your house keys, and your friend just shouted at you. You meet an acquaintance in the corridor; they say, “how are you?” You say, “fine thanks, and you?”.
    4. Your gran has saved up her pension, bought some wool, and knitted you a jumper. You hate it. She is visiting you and you put it on. She asks, smiling, “so, do you really like it?” You reply, “of course Gran, thanks so much for thinking about me”.
    5. You are taking a maths test and one question asks the solution to sinx2 + cosx2 You write “10” [the answer is “1”].
    6. A recent divorcee keeps wearing his wedding ring.
    7. You are smuggling Bibles into China. At the border, the guards ask you what you have in your truck. As it happens, you have hundreds of Bibles, so you say “oh, hundreds of Bibles”. The guards think this is a joke and wave you through.

    So what do you think? Are these cases of lying or not? Let’s take them in turn.

    (1) This does not fall into the category of lying as there was no intent on your part to mislead your friend.

    (2) Is harder. Strictly speaking atoms are nothing like footballs; they are, for example, mostly space. And as Kirsten Walsh and Adrian Currie1 state “the truth, the whole truth and nothing but the truth, is no teacher’s maxim”. This is because it is simply impossible to go into all the details of science or history, or chemistry etc. But does this mean that you are lying to the class? We think the answer is “yes” and in fact all teaching involves lying. Of course, whether this is right or wrong is something that we’ll return to below.

    (3) Arguably this would not be categorised as lying as the reply given is generally considered to be a standard answer to a standard question; the questioner would be expecting this reply in most circumstances.

    (4) This does seem as if it is a clear case of lying. Having been asked a direct question by your gran, you look her in the eye and lie. Now whether this is wrong is something we consider below; it would seem that it is precisely for cases such as this that we have the phrase “little white lie”.

    (5) This does not seem to be a case of lying, rather just bad maths. It is certainly false but there is no lie involved.

    (6) This could be a case of lying. If the social context is one in which we understand that wearing a wedding ring indicates that someone is married, then wearing a wedding ring when you are not married seems like a case of lying.

    (7) This does not seem like a case of lying as you were completely honest in your reply to the guard. However, if there was an intention to deceive then this may not be the case. But as it stands (7) is not a case of lying.

    What then can we take from these quick examples?

    Lying does not simply involve saying something false. That is what (5), the maths case, shows us.

    Lying can involve things other than speaking; it can involve writing, signs and symbols; that is what (6) — the wedding ring — shows us.

    In cases such as (3), even if we say something we know to be false, it is not necessarily thought to be a lie as the intention to deceive is missing.

    That is why “yes I like the jumper Gran” in (4) is a lie. You intend that your Gran adopt the false belief that you do like the jumper.

    Notice finally that in the Bible smuggling case if the person knew that by telling the truth — “yes there are Bibles in the truck” — then the guards would form the false belief that there were no Bibles in the truck, then this might count as lying. So for something to be a lie, what is important is the intention to deceive — but it need not be the case that what is being said is false.

    Of course, all these claims are controversial but they at least give us some starting points for thinking about the moral question.

    Finally, as an aside, it is a controversial and philosophically interesting question whether we can lie to ourselves. We do not discuss this here but “not lying to oneself” is a common phrase used by psychologists, self-help books, counsellors etc. It is then a genuinely interesting question which deserves consideration at some point — just not here.

    We can now frame the moral question like this. When, if ever, is it morally acceptable to intend for someone to adopt a belief which you know to be false?

    Let’s consider this question through the lens of some of the theories already discussed in this book.

    3. Utilitarianism

    If you recall (Chapter 1) Consequentialism has two features. First is the definition of “good (happiness, pleasure, well-being, preferences etc.) and then the consideration of right and wrong actions in relation to good. In particular, an action is right if, and only if, it brings about the greatest amount of happiness, pleasure, well-being, preference satisfaction etc.

    The second feature is that everyone counts as equal in the calculations. That is, your good is as important as my good, which is as important as anyone else’s good.

    It follows from these two claims that no action is morally right or wrong irrespective of context. So we cannot say that lying is wrong because the action of lying will only be wrong if it brings about less good than not doing so. If I intend that you adopt a belief which I believe to be false but in so doing I generate more good than if I had not, then I have done something right.

    Utilitarianism seems to be intuitive in some cases. Imagine, for example, a soldier captured and tortured but who still continues to lie and say that she does not know how to break the allies’ codes, and in so doing she saves hundreds of thousands of lives. In this case people believe that she was right to have lied; given the horrific consequences of telling the truth she is morally required to lie. However, the intuitions work both ways and there are cases where we think that sometimes it is morally counterintuitive to be required to lie.

    Consider a famous example from H. J. McCloskey known as “McCloskey’s Sheriff”.2

    Imagine a scenario where there has been a serious crime in a town and the Sheriff is trying to prevent serious rioting. He knows that this rioting is likely to bring about destruction, injury and maybe even death. The problem is that he has no leads; he has not the slightest idea who committed the crime. However, he can prevent these riots by lying to the town and framing an innocent man. No one will miss the man and he is hated in the town. If he frames and jails this innocent man, convincing people to believe that it was this man that committed the crime, then the town will be placated and people will not riot. The consequentialist will judge in this case that it is morally required that the Sheriff lies even if this means that an innocent man is jailed. This then shows that the fact that the consequentialist says it is sometimes morally required to lie can lead to counterintuitive conclusions.

    Let’s consider a mundane case. If lying to your gran brings about the best consequences — i.e. she is happy, you are happy, and she continues to knit which makes her happy etc., then it is morally acceptable to lie. Notice, however, that the consequentialist would say that we ought to lie; not just that it is acceptable to lie but that we have a moral obligation to lie.

    Of course, the utilitarian should try and think harder about the possible consequences and outcomes in order to try and prevent some new problems arising. Consider the sheriff example; it could be that the real criminal confesses resulting in worse consequences than if the truth had been told at the outset. Now, not only will there be riots but there will also be no trust in the law enforcement. So, in fact, lying would bring about worse consequences, which means it would be wrong to lie.

    Or consider the gran example. If your brother tells his gran that you lied, then we can imagine that this might mean she would not be able ever to trust her grandchildren again, may give up knitting, and thus make her unhappier than if she had originally been told the truth about the jumper.

    However, because no action is right or wrong qua action in Utilitarianism, it follows that the action of lying is neither wrong nor right. So to the question “does the utilitarian think that lying is wrong?” the answer is “it just depends”.

    4. The Kantian and Lying

    In contrast the Kantian (see Chapter 2) claims that actions are wrong or right, qua actions. So rather than first defining good and then defining the right and wrong actions they first define right and wrong. How they might do this will depend on what type of deontologist they are. The Kantians ground the rightness and wrongness on reason. In particular, we introduced one version of Kant’s Categorical Imperative. We can show, using this, that Kant — and in fact all deontologists — think that the action of lying is wrong in all cases. Even if the consequence is saving a billion people, your own mother or an orphanage of children.

    It is worth noting that in the other Kantian formula that we introduced, lying also comes out as wrong. Kant said that we should always treat others as an end in themselves, and never solely as a means to an end. We can see that this makes lying wrong. For if we lie to someone then we are not treating them as an end in themselves but are controlling what they can do by taking certain decisions out of their hands; we are basically saying we should be allowed to deceive them for our own ends. We are not treating them as rational agents and for the Kantian this is always morally wrong.

    This might seem counterintuitive, and it is. However, it is perhaps less so if we revisit our definition of lying. Go back to the soldier case. Imagine she is being tortured for military codes. It seems that one way to stop the consequence that hundreds of thousands of people die would be simply to say nothing. And, given our definition, saying nothing would not be lying. So the Kantian may not be committed to the implausible conclusion that she has to reveal the secrets. Keeping silent is not the same as lying.

    Furthermore, it is worth remembering that there are different ways of telling the truth! Saying to your gran: “I really appreciate all the work you’ve put in to my jumper, and my friend thinks it is an amazing jumper, but it really is not my style, I’m really sorry”, seem less objectionable than “No, I do not like it”.

    So there are — maybe — ways of making Kant’s theory less objectionable when considering lying by thinking harder about what it actually means to lie. Even so, it seems undeniable that there are some cases where we think it is morally acceptable to lie but for the Kantian there are no such cases.

    Notice that it is not just the Kantian that would say this. Other deontological theories would as well. For example, the Divine Command Theory, the theory that says that actions are right or wrong depending on whether God commands or prohibits them. If God says lying is wrong — and at least in the main monotheistic religions He does — then it is, full stop. Or consider the Catholic theologian Aquinas.

    5. Some Final Thoughts about the Political Context

    As we write, Donald Trump has just been elected as US president. Whether you agree with his policies or not, what has been interesting is how the presidential campaign has been run; in particular, it has put under serious doubt our initial claim above, namely, that lying in public office is something to be avoided at all costs. However, Trump seems unaware and uninterested in truth — hence some people have suggested that he has ushered in a “post-truth” era.3 This era seems to be created in part because of the propagation of false news stories on social media sites — so much so that Facebook and other social media groups have been working on ways to alert people to “fake news”.

    Thus, the questions we leave you with are whether you think that it makes sense to talk about lying in the political “post-truth” era. When Trump says “I won the popular vote because millions of people voted illegally” is this a lie? We do not mean is it true, because it is patently false. We mean do you think the concept of a lie has changed throughout time? Has the political landscape changed so dramatically that the concept of lie has no currency? Related, what is the moral status of lying? If politicians and constituents do not care about the truth, then does this affect the moral status of lying (at least in the political arena)? We do not attempt to answer these questions here but they show, as if we need reminding, that the moral status of lying is of vital importance at the local, national and international levels.


    Philosophers, in many issues, like to start by asking what we mean by the key term. Once we ask the question “what is it to lie?” it becomes quickly apparent that the issues are complex and unclear. To lie does not just mean to say something false, rather it has something to do with trying to get another person to believe what you claim to be true, when you in fact think it is false.

    Different theories we have looked at so far in this book have different responses to the question “is it wrong to lie”? The utilitarian says “it depends”. That is, if the consequences of lying are better than telling the truth then we are morally required to lie. The deontologist — the Kantian or Divine Command Theorist for example — thinks that lying is always wrong. There are no situations at all when it would be morally acceptable to lie.

    Both the consequentialist and the deontologist’s responses seem to lead to counterintuitive claims. One possible way to respond to this is to revisit the definition of lying and claim that the counterintuitive responses to moral questions regarding lying arise because of a false or incomplete understanding of what it is to lie.

    Finally, we might simply reject the requirement of capturing our intuitions at all. We might simply say, so much the worse for our intuitions! We finished this chapter with some general thoughts about truth and lying in the political arena.


    • Thinking that Kant says that we should always tell the truth. Whereas in fact he says it is wrong to lie.
    • Thinking that the utilitarian says that if a lie leads to pleasure then it is morally acceptable to lie.
    • Mistaking being nasty with being immoral.
    • Thinking that you require words to lie.


    1. Read (1)–(7) at the start of this chapter. Do you think these are cases of lying or not? Give reasons for your answers.
    2. Do you ever think it is morally acceptable to lie? When?
    3. Could a robot lie?
    4. In the local town there is a sign at the roundabout — “Happy birthday Keith, 40 today!” It has been there about a year. Is this lying?
    5. Do you think it makes sense to talk about “lying to oneself”? If it does, how might this change our definition?
    6. Reflecting on your answers so far would you agree with our definition of “lying”? Or do you think it needs modifying?
    7. Give an example where the consequentialist would say we are morally required to lie.
    8. How might the rule and the act utilitarian differ in their response to the question whether it is morally wrong to lie?
    9. Give an example where the deontologist would say we ought not to lie.
    10. If you had to go for either a deontological approach to lying or a consequentialist approach, which would it be?
    11. Do you think that we are living in a “post-truth” era? If so, how does this change (if at all) how we think of lying?



    McCloskey’s Sheriff





    McCloskey, H. J., ‘A Non-Utilitarian Approach to Punishment’, in Philosophical Perspectives on Punishment, ed. by Gertrude Ezorsky (Albany: State University of New York Press, 1972), 119–34.

    Walsh, Kirsten and Adrian Currie, ‘Caricatures, Myths, and White Lies’, Metaphilosophy, 46.3 (2015): 414–35.

    1 K. Walsh and A. Currie, ‘Caricatures, Myths, and White Lies’, p. 424.

    2 McCloskey, ‘A Non-Utilitarian Approach to Punishment’. for 101 of his lies.

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