ARE THERE MORAL TRUTHS? Bart Streumer b.streumer@rug.nl 30 June 2020 A brief overview of metaethics, written for students We all think that some actions are morally permissible and other actions are morally impermissible. But we also have moral disagreements: for example, some of us think euthanasia is permissible, but others think euthanasia is impermissible. Is there a truth of the matter in such disagreements? On the one hand, we seem to assume that there is. For we do not treat moral disagreements the way we treat disagreements about purely subjective issues. If I think peanut butter is tasty but you think it is disgusting, we are unlikely to regard each other as mistaken or to try to find out who is right. But if I think euthanasia is permissible and you think it is impermissible, we probably will regard each other as mistaken. Moreover, we may try to find out who is right by discussing the pros and cons of euthanasia. This suggests that we take there to be a truth of the matter in moral disagreements. On the other hand, however, it is easy to raise doubts about the existence of such truths. For what could make it the case that there are moral truths? And how do we find out what they are? Metaethics is the part of philosophy that investigates these issues.1 It focuses on three main questions: • Are moral thoughts beliefs or are they attitudes of some other kind? 1 It is called 'metaethics' because whereas ethics asks moral questions, such as whether euthanasia is permissible, metaethics asks questions about these moral questions and about the answers we give to these questions. 2 • If moral thoughts are beliefs, are any of these beliefs true? • If some of these beliefs are true, how do we find out which of them are true? In this chapter, I will give a brief overview of the answers that metaethicists give to these questions. In sections 1 to 3, I will discuss three simple answers. In section 4, I will discuss more sophisticated versions of these answers. These more sophisticated versions are quite similar to each other, but in section 5 I will show that there is at least one issue that continues to divide them. 1. Cognitivism and non-cognitivism I will start with the first question: are moral thoughts beliefs or are they attitudes of some other kind? According to cognitivism, moral thoughts are beliefs. For example, according to cognitivism, if I think euthanasia is permissible, I have a belief that ascribes the property of being permissible to euthanasia.2 My belief is true if euthanasia has this property and false if it does not have this property. And if you think euthanasia is impermissible, you have a belief that ascribes the property of being impermissible to euthanasia. As before, your belief is true if euthanasia has this property and false if it does not have this property. If we assume that euthanasia cannot have both of these properties, cognitivism entails that our beliefs cannot both be true. By contrast, according to non-cognitivism, moral thoughts are not beliefs but attitudes of some other kind.3 For example, according to a simple version of non-cognitivism, if I think 2 A property is a feature something has. For example, as another way of saying that I am a philosopher, we can say that I have the property of being a philosopher. In a similar way, if cognitivism is true, as another way of saying that euthanasia is permissible, we can say that euthanasia has the property of being permissible. For an overview of the debate about the nature of properties, see Edwards 2014. 3 Non-cognitivists often call these attitudes 'non-cognitive attitudes' or simply 'attitudes'. For an overview of the debate between cognitivists and non-cognitivists, see Schroeder 2010 and van Roojen 2018. 3 euthanasia is permissible, I have an attitude of approval towards allowing euthanasia.4 And if you think euthanasia is impermissible, you have an attitude of disapproval towards allowing euthanasia. Simple versions of non-cognitivism deny that these attitudes ascribe properties and therefore deny that moral thoughts can be true or false. Of course, if I believe that I approve of an action, this belief can be true or false. But non-cognitivism does not say that moral thoughts are beliefs about our attitudes: it does not say, for example, that my thought that euthanasia is permissible is the belief that I approve of allowing euthanasia.5 Instead, it says that moral thoughts are themselves attitudes of approval or disapproval. One reason to think that non-cognitivism is true is that we are normally motivated to act in accordance with our moral thoughts. If I say that lying is wrong but you notice that I tell lies all the time, you will probably conclude that I do not really think lying is wrong: if I really thought this, I would be motivated to avoid lying. This connection between moral thoughts and motivation is easy to explain if non-cognitivism is true, since attitudes of approval or disapproval can clearly motivate us. But the connection is harder to explain if cognitivism is true, since beliefs normally do not motivate us all by themselves. For example, if I say that I believe there is milk in the fridge, you do not yet know what I am going to do. To know this you also need to know something about my other attitudes: for example, whether I am feeling thirsty and whether I like milk. Non-cognitivists often take this to show that moral thoughts are not beliefs but are instead attitudes of some other kind. But there are also several reasons to think that cognitivism is true. The first, which is known as the Frege-Geach problem, is as follows. Suppose you want to argue that euthanasia is impermissible. You could then give the following argument: Killing people is impermissible. If killing people is impermissible, euthanasia is impermissible. So euthanasia is impermissible. 4 This simple version of non-cognitivism is known as emotivism. See Ayer 1946. 5 The view that moral thoughts are beliefs about our attitudes is often called subjectivism. There are also other versions of subjectivism. 4 Cognitivists can explain why this argument is valid: they can say that this argument is valid because it is impossible that its premises are true (in other words, that it is true that killing people is impermissible and that it is true that if killing people is impermissible, euthanasia is impermissible) and that its conclusion is false (in other words, that it is false that euthanasia is impermissible). For according to cognitivism, these premises and this conclusion express beliefs that can be true or false. But it is much harder for defenders of simple versions of noncognitivism to explain why this argument is valid, since they deny that moral thoughts can be true or false. That is a reason to reject simple versions of non-cognitivism. As we will see in section 4, however, more sophisticated versions of non-cognitivism aim to solve this problem. A second reason to think that cognitivism is true is that this view is easier to square with the objectivity that we attribute to morality. Suppose again that I think euthanasia is permissible and that you think it is impermissible. Cognitivists can say that these thoughts cannot both be true, since euthanasia cannot have both the property of being permissible and the property of being impermissible. They can therefore say that we really disagree. But defenders of simple versions of non-cognitivism cannot say that we disagree in this way. They often say that we disagree in a different way: we have clashing attitudes of approval and disapproval and these clashing attitudes may make us do incompatible things. For example, my attitude may make me campaign for a law that allows euthanasia and your attitude may make you campaign against this law. But if I like peanut butter and you dislike it, we also have clashing attitudes that may make us do incompatible things: for example, my attitude may make me buy peanut butter and your attitude may make you throw it in the bin. This kind of clash seems very different from a moral disagreement. Moreover, if we disagree with a Nazi who says that Hitler was morally admirable, we do not take this to be a purely subjective issue, like clashing attitudes towards peanut butter. Instead, we take the Nazi's view to be mistaken in a way that goes beyond clashing attitudes. That is another reason to reject simple versions of non-cognitivism. As before, however, we will see in section 4 that more sophisticated versions of non-cognitivism aim to solve this problem. 2. Realism Suppose for now that cognitivism is true: in other words, suppose that moral thoughts are 5 beliefs. We should then ask our second question: are some of these beliefs true? If moral thoughts are beliefs, they are true if the actions to which these beliefs ascribe moral properties, such as the property of being permissible or the property of being impermissible, really have these properties.6 This means that moral thoughts can only be true if these properties exist. According to realism, moral properties do exist and certain actions therefore have these properties.7 But realists disagree about the nature of these properties. According to naturalist realists, moral properties are natural properties, by which they mean that these properties can in principle be discovered via empirical investigation.8 Naturalist realists often note that our use of moral terms, such as the term 'permissible', is regulated by certain natural properties: in other words, that when an action has a certain natural property, this tends to make us apply the term 'permissible' to that action. And they often say that a moral term like 'permissible' ascribes the natural property that regulates its use: in other words, that the property that the term 'permissible' says an action has is the natural property that tends to make us apply this term to an action. For example, suppose that I think an action is right if and only if it maximises happiness. My use of the term 'permissible' is then regulated by the natural property of maximising happiness. Naturalist realists can then say that the term 'permissible', as I use it, ascribes the natural property of maximising happiness.9 The main reason to think that naturalist realism is true is that this view fits moral properties into a naturalistic picture of the world. This makes it very likely that moral properties exist and that some moral thoughts are true. Moreover, it also helps to answer our third question: how do we find out which moral thoughts are true? For if naturalist realism is 6 Some cognitivists deny that moral properties are needed to make moral thoughts true: see, for example, Korsgaard 2008. For discussion, see Enoch 2006. 7 This raises the question how many moral properties exist: in addition to a property of being permissible and a property of being impermissible, are there also a property of being obligatory, a property of being a reason, a property of being good, a property of being bad, and so on? Most realists think there are many moral properties, but that their existence can be explained in terms of a few core moral properties, such as perhaps the property of being a reason. 8 This view is defended, for example, by Boyd 1988 and Brink 1989. 9 Not all naturalist realists defend their view in this way. For other strategies, see Jackson 1998 and Schroeder 2007. For an overview, see Lenman and Lutz 2018. 6 true, we can find out which of these thoughts are true via empirical investigation. For example, if the term 'permissible' ascribes the property of maximising happiness, we can find out whether euthanasia is permissible by investigating whether allowing euthanasia maximises happiness.10 But we can only do this if we already know which natural property the term 'permissible' ascribes. That is why many naturalist realists say that moral terms like 'permissible' ascribe the natural properties that regulate their use: because this enables us to find out via empirical investigation which natural properties moral terms ascribe. But there are also reasons to think that naturalist realism is false. One reason to think this is that this view has relativistic implications.11 For suppose that our use of the term 'permissible' is regulated by different natural properties: for example, suppose that my use of this term is regulated by the property of maximising happiness and that your use of this term is regulated by the property of maximising happiness without killing anyone. If moral terms ascribe the natural properties that regulate their use, the term 'permissible' as I use it and the term 'permissible' as you use it then ascribe different properties. This entails that when I think euthanasia is permissible and you think it is not permissible, our thoughts can both be true, since allowing euthanasia may have the property of maximising happiness but lack the property of maximising happiness without killing anyone. It therefore entails that when I think euthanasia is permissible and you think it is not permissible, we do not really disagree. This makes naturalist realism hard to square with moral objectivity. Many realists are therefore instead non-naturalist realists: they think that moral properties are non-natural properties, by which they mean that these properties cannot be discovered via empirical investigation.12 If non-naturalist realism is true, there is a truth of the matter in moral disagreements: if I think euthanasia is permissible and you think it is not permissible, my belief ascribes the non-natural property of being permissible to euthanasia 10 We may doubt that this property can regulate my application of the term 'permissible', since it is hard to know which actions maximise happiness. But I only use this property as an example here. 11 See Horgan and Timmons 1991. Their version of this reason to reject naturalist realism is known as the Moral Twin Earth argument. 12 This view is defended, for example, by Shafer-Landau 2003 and Enoch 2011. For an overview, see Ridge 2019. 7 and your belief denies that euthanasia has the very same non-natural property, which means that at most one of our beliefs can be true. Non-naturalist realism therefore fits better with moral objectivity. That is the main reason to think that this view is true. But there are also reasons to think that non-naturalist realism is false. One reason to think this is that this view does not even try to fit moral properties into a naturalistic picture of the world.13 Instead, non-naturalist realists say that moral terms like 'permissible' ascribe non-natural properties that are completely different from the ordinary properties that we can discover via empirical investigation. They therefore have trouble answering our third question: how do we find out which moral thoughts are true? If moral thoughts ascribe nonnatural properties, we clearly cannot find out which of these thoughts are true via empirical investigation. Many non-naturalist realists instead think that certain moral truths are selfevident, by which they mean that understanding these truths gives us sufficient reason to believe these truths. For example, perhaps it is self-evident that happiness is good, since understanding the claim that happiness is good may give us sufficient reason to believe it. But if there are self-evident moral truths, it is surprising that there is so much disagreement about what these truths are.14 That is not the case for other seemingly self-evident truths, such as fundamental mathematical truths. A second reason to think that non-naturalism is false is that if moral properties are non-natural, they do not seem to play any role in explaining why we have the moral thoughts that we have.15 Suppose again that I think euthanasia is permissible and that you think it is impermissible. What explains why we have these different moral thoughts? Is the best explanation that one of us has recognised a self-evident moral truth and that the other has not, and that as a result of this we ascribe different non-natural properties to euthanasia? Or is the best explanation that we have been brought up in different ways and are part of different 13 See Mackie 1977. His version of this reason is known as the argument from queerness. 14 We may agree that certain claims are moral truths if they are formulated imprecisely, like the claim that happiness is good: this claim does not say what happiness consists in, to what extent happiness is good compared to other good things, and so on. But the more precisely such claims are formulated, the more we seem to disagree about them. 15 Again, see Mackie 1977. His version of this reason is known as the argument from relativity. 8 social environments, and that as a result of this we respond differently to the natural properties of euthanasia? On the face of it the second explanation seems more plausible than the first. And if non-natural properties play no role in explaining why we have the moral thoughts that we have, that is a reason to doubt that these properties exist. 3. The error theory Suppose that the reasons I have outlined in sections 1 and 2 show that cognitivism is true but that realism is false. If so, moral thoughts are beliefs, but the properties that these beliefs ascribe do not exist. This view is known as the error theory.16 If the error theory is true, no action is impermissible, since the property of being impermissible does not exist. But no action is permissible either, since the property of being permissible also does not exist.17 More generally, the error theory entails that all moral thoughts are false, since none of the properties that these thoughts ascribe exist. Can that really be the case? Perhaps it can. For we have seen in sections 1 and 2 that there are reasons to think that cognitivism is true and that realism is false, and these reasons together support the error theory. But there are also reasons to think that the error theory is false. One reason to think this is that if we came to believe this theory, we would probably still think that some moral thoughts are more acceptable than others. For example, consider the thought that murder is permissible and the thought that murder is impermissible. If we all started to think that murder is permissible, it would be hard to continue to live together peacefully. If we came to believe the error theory, we would therefore probably still think that the thought that murder is impermissible is more acceptable than the thought that murder is permissible. But if that is so, why should we think that moral thoughts are true only if the actions to which they ascribe a moral property really have this property? Why should we not instead think that moral 16 This view is defended, for example, by Mackie 1977, Joyce 2001, Olson 2014, and Streumer 2017. For an overview, see Joyce 2016. 17 Defenders of the error theory must deny that 'not impermissible' entails 'permissible', since otherwise their view contradicts itself. 9 thoughts are true if their general acceptance enables us to live together peacefully? In that case, some moral thoughts are true, which entails that the error theory is false.18 Another reason to think that the error theory is false is that this theory entails some extremely implausible claims.19 For example, the theory entails that torturing babies for fun is not impermissible. But the thought that torturing babies for fun is impermissible is surely much more plausible than any philosophical theory could ever be. And if torturing babies for fun is impermissible, this means that at least one moral thought is true, which entails that the error theory is false.20 That seems an extremely convincing reason to reject the error theory. As I have said, however, the reasons to think that cognitivism is true and that realism is false that I discussed in sections 1 and 2 together support the error theory. To really establish that this theory is false, we therefore need to do more: we need to undermine these reasons to think that cognitivism is true and that realism is false. 4. More sophisticated versions of these views Non-cognitivists and realists try to undermine these reasons by defending more sophisticated versions of their views. I will now give a brief overview of these more sophisticated versions. Non-cognitivists propose solutions to the Frege-Geach problem. Consider again the following argument: Killing people is impermissible. If killing people is impermissible, euthanasia is impermissible. So euthanasia is impermissible. Suppose that the first premise of this argument expresses disapproval of killing people and that the conclusion expresses disapproval of allowing euthanasia. Non-cognitivists can try to explain why this argument is valid by explaining which attitude is expressed by the second 18 See Wright 1992 for an argument along these lines. 19 See Dworkin 1996 and Nagel 1997 for arguments along these lines. 20 At least, if we assume that moral thoughts are beliefs. But that is what the error theory assumes. 10 premise: in other words, by the claim that If killing people is impermissible, euthanasia is impermissible. Perhaps this premise expresses disapproval of the following state of mind: disapproving of killing people while not disapproving of allowing euthanasia. In that case, someone who accepts both premises of this argument disapproves of killing people and also disapproves of disapproving of killing people while not disapproving of allowing euthanasia. If this person does not accept the conclusion of the argument and thereby does not disapprove of allowing euthanasia, this person disapproves of their own state of mind. That gives us a sense in which this argument is valid, though its validity is different from the validity of non-moral arguments.21 Non-cognitivists have also tried to square their view with moral objectivity. As I said in section 1, if we disagree with a Nazi who says that Hitler was morally admirable, we think the Nazi's view is mistaken in a way that goes beyond clashing attitudes. Non-cognitivists can say that the thought that the Nazi's view is mistaken in this way is itself an attitude of approval or disapproval: for example, they can say that this thought is an attitude of disapproval of the Nazi's approval of Hitler. More generally, non-cognitivists can say that the thought that morality is objective is an attitude of disapproval of attitudes of approval or disapproval that differ from our own.22 Since this enables us to say that other people's views are mistaken, it gives us a sense in which morality is objective, though this objectivity is different from objectivity in other areas of thought. When non-cognitivists develop their view in these ways, they move it closer to realism. Some non-cognitivists even call themselves quasi-realists: they think that by solving the Frege-Geach problem and squaring their view with moral objectivity, they earn the right 21 This is just one possible solution to the Frege-Geach problem, which is proposed by Blackburn 1993. For other possible solutions, see Gibbard 2003 and Schroeder 2008. For discussion, see Schroeder 2010 and van Roojen 2018. 22 Moves along these lines are made by Blackburn 1993. 11 to say that there are moral truths and moral properties.23 But they disagree with realists about what this involves. Quasi-realists think that the sentence "It is true that euthanasia is permissible" expresses the same attitude as the sentence "Euthanasia is permissible", and that all it takes for euthanasia to have the property of being permissible is for the sentence "Euthanasia is permissible" to be true. Most realists disagree: they think that for euthanasia to be permissible, it must have a real moral property that consists in more than just the truth of a sentence. But some realists do borrow elements of non-cognitivism. For example, some naturalist realists say that even though moral thoughts are beliefs that ascribe natural properties, these beliefs are accompanied by attitudes of approval or disapproval towards the actions that have these properties.24 Suppose again that our use of the term 'permissible' is regulated by different natural properties: as before, suppose that my use is regulated by the property of maximising happiness and that your use is regulated by the property of maximising happiness without killing anyone. Naturalist realists who develop their view in this way can say that when I think euthanasia is permissible and you think it is impermissible, we disagree in the sense that our moral thoughts are accompanied by clashing attitudes of approval or disapproval. And they can say that these accompanying attitudes explain why we refuse to call the Nazi's view that Hitler was morally admirable 'true': we are only willing to apply the term 'true' to someone's view if we share their attitudes of approval or disapproval. Moreover, some non-naturalist realists borrow elements of quasi-realism. When it is pointed out to them that non-natural properties do not fit into a naturalistic picture of the world, they insist that all they mean when they say that there are non-natural properties is that certain actions are permissible and other actions are impermissible.25 And they follow quasirealists in saying that a sentence like "It is true that euthanasia is permissible" expresses the same belief as the sentence "Euthanasia is permissible", and that all it takes for euthanasia to have the non-natural property of being permissible is for the sentence "Euthanasia is 23 See Blackburn 1993. 24 See, for example, Copp 2001. Ridge 2014 and Finlay 2014 also defend views that combine elements of naturalist realism and non-cognitivism. 25 See Scanlon 2014 for claims along these lines. 12 permissible" to be true. Such non-naturalist realists are known as quietists. Finally, most error theorists think that we should not give up our moral thoughts if we come to believe the error theory. Instead, they think, we should change the nature of these thoughts: we should replace them with attitudes of approval or disapproval or with beliefs that ascribe natural properties.26 And they think we should continue to use sentences like "Euthanasia is permissible" to express these new attitudes or beliefs. The error theory would then still be true about our old moral thoughts, but it would be false about our new moral thoughts: instead, non-cognitivism or naturalist realism would be true about these new thoughts. Other error theorists argue that we do not need to change anything about our moral thoughts, either because keeping our current moral thoughts is the best way to live together peacefully, or because we cannot believe the error theory and the arguments for the theory therefore cannot make us change the nature of our moral thoughts.27 This moves the error theory closer to other metaethical views. 5. What divides these views? The more sophisticated versions of non-cognitivism, realism and the error theory that I discussed in section 4 are more similar to each other than the simple versions that we started with. But there is at least one issue that continues to divide these views. Suppose again that I think euthanasia is permissible. But now suppose that everyone else agrees. Moreover, suppose that allowing euthanasia has the natural property of maximising happiness, that everyone's use of the term 'permissible' is regulated by this natural property, and that everyone has an attitude of approval towards all actions that have this natural property. Is that enough for my moral thought to be true? In other words, is it enough for it to be true that euthanasia is permissible? Naturalist realists think it is. For according to the simple version of this view that we started with, if allowing euthanasia has the natural property that regulates my use of the term 26 See Joyce 2001 and Lutz 2014. 27 See Olson 2014 for the first kind of argument and Streumer 2017 for the second kind of argument, applied to a more general error theory. 13 'permissible', then my moral thought is true. And according to the more sophisticated version that I outlined in section 4, if allowing euthanasia has the natural property that regulates everyone's use of this term and everyone has an attitude of approval towards all actions that have this property, then my moral thought is true as well. By contrast, most non-naturalist realists deny that what I have described above is enough for my moral thought to be true. Instead, they think that my thought is true only if euthanasia has another property in addition to its natural properties: the non-natural property of being permissible. And error theorists agree. Their disagreement with non-naturalist realists is not about whether this additional property is needed to make my moral thought true, but only about whether this additional property exists: non-naturalist realists think it does, but error theorists think it does not. What quasi-realists and quietists think is less clear. They could say that what I have described above is enough for my moral thought to be true. But in that case, non-naturalist realists who are not quietists will say that these views do not really fit with moral objectivity. Alternatively, quasi-realists and quietists could say that what I have described above is not enough for my moral thought to be true: instead, they could say, this thought is true only if euthanasia has the additional non-natural property of being permissible. But in that case, error theorists will say that the reasons to reject non-naturalist realism are also reasons to reject quasi-realism and quietism. Is what I have described above enough for it to be true that euthanasia is permissible? Are natural properties, regulation by these properties, and attitudes all we need? That is perhaps the central question in metaethics right now. Whether there are moral truths depends on how we answer it.28 References Ayer, A. J. 1946. Language, Truth and Logic (second edition). 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