Some believers think the existence of objective moral rules and values is evidence for a god. The so-called argument from objective morality is a mistake. But to see why, it helps to clarify what morality is in the first place.
Morals are rules for how we should treat each other, such as: be kind and do no harm. Most of us learn them, or the behaviour they promote, from early childhood. And they are universal because a society is unlikely to thrive, or even exist for long, without them.
Rules are instructions, and they have no truth value. In their simplest form, they are commands. And it makes no sense to say a command such as do no harm is either true or false. That would be to misunderstand its purpose.
Commands such as be kind and do no harm are in the present tense. And this is significant when it comes to understanding the purpose of moral assertions.
We can always express a moral rule in the form of an assertion, using the words right and wrong or good and bad. For example: harming others is wrong and it is good to be kind. Or we may say it is true that we should be kind. But this is to use the word true in a non-factual way, usually to emphasise agreement.
Factual assertions describe features of reality. For example, we make assertions about the way we treat or treated each other. As usual, those assertions may be true or false. And they need the usual objective justification in the form of evidence.
By contrast, moral assertions are judgements about the way we should treat each other. They are prescriptive rather than descriptive. And they express judgements which are, or are supposed to be, universal – not restricted to a particular place or time period.
For example, if it is good to be kind, then it always was and will be good. Moral assertions are in a kind of timeless present tense. Or they could be described as tenseless. We do make moral judgements about past events. But the reason why, for example, it was wrong to harm others, is that it is wrong.
Another feature of moral assertions is that they are general guides which we have to apply in specific circumstances. Moral conduct is always situational, and there can be moral dilemmas with conflicts of interest. For example, in war or extreme self-defence, harming others may be morally justifiable.
Moral rules are rational, because there are sound reasons for having and following them. For example, we all have a practical need for food, clothes, shelter, healthcare, education, life chances, freedom from harm, and so on. So making sure everyone has them is morally good, and, normally, to deprive people of them is immoral.
Many of us would add such things as love and friendship, company, fulfilment, self-esteem and social prestige, and so on. And many of us would give these goods a high priority. The list is not fixed, and the choices are open to rational debate. But individual well-being is the common factor.
To put it simply: actions that promote the well-being of others are morally good, and normally those that harm others are immoral. But of course, there can be rational debate about the consequences of any action.
To be subjective is to rely on personal opinion. By contrast, to be objective means to rely on facts, which are true regardless of what anyone believes or claims to know, and regardless of their source. In effect, objectivity excludes subjectivity of any kind. It frees each of us from our own and other people’s opinions and interests.
Because it is based on facts about well-being, morality is objective. And, for this reason, far from showing there is a god, the existence of moral objectivity means a god (or any other agent) is morally irrelevant.
For example, rape is objectively wrong, because it harms the well-being of the victim. So the existence of a god, and its nature and commands, have no bearing on the immorality of rape. The theistic argument from objective morality is self-defeating. Its premise, objective morality can only come from a god, mistakes the nature of objectivity.
(Incidentally, the factual basis to morality may explain why some people believe there are moral facts. It is an understandable misunderstanding.)
It is because morality has an objective basis that we can morally judge other people’s and our ancestors’ beliefs and behaviour.
It is objectively wrong to commit or incite genocide; subjugate women; enslave people; genitally mutilate children; persecute or murder homosexuals, heretics, apostates and non-believers; stone adulterers and burn witches; perform or permit a human sacrifice – to name some of the atrocities either commanded or endorsed in one or more of the Abrahamic scriptures.
These actions were and remain immoral, whatever our ancestors may have thought, and whatever they imagined their god wanted them to do. To understand why inquisitors committed, or jihadists commit, appalling crimes is not to excuse them. Morality really is objective.
The divine command theory is that morality is not objective. Rather, we supposedly have moral rules only because a god gave them to us and commanded us to obey them. One source of the theory is a Biblical myth about our fallen nature, which makes us incapable of consistent moral judgements and behaviour – hence the need for commandments.
Some believers take this theory seriously: If there is no god, how can we tell right from wrong? Without a god, anything goes. So, at the risk of repetition, it is important to spell out the fallacies.
First: the theory assumes there is a god, which is objectively unjustified. There is no evidence for any factual assertion of a god, or the divine source of any scripture or any other revelation. Like all assertions of the supernatural, the divine command theory does not even make it to the starting post.
Second, there is a practical problem: which god are we talking about? To make sense, the theory has to assume there is one god whose commands we must obey; that one particular scripture is the inspired word of that god; and that that scripture contains the commands of that god. None of these assertions is objectively justified.
Third: because it is based on facts, morality is objective. So its source, spoken or written, human or divine, is irrelevant. The assertion this is good because I say it is has no place in a rational moral debate, so nor does this is good because a god says it is. Such an appeal to authority is as fallacious for moral as it is for factual assertions.
Fourth: there is a natural, evolutionary explanation for our moral rules. Love for our children and parents, reciprocity, altruism and self-denial, co-operation with others increasingly distant from the family – all of these are explicable in terms of individual well-being and social development. Apart from being self-defeating, the assertion objective morality can only come from a god is also factually false.
Aware that the divine command theory of morality is a mistake, some believers claim that instead morality is rooted in their god’s nature. But as there is no evidence for any god in the first place, to claim to know its nature is irrational. An irrational premise cannot lead to a rational conclusion.
Because morality is objective, it is not relative to or dependent upon personal or even group opinion. For example, even if everyone believed it right to discriminate against foreigners, it would still be immoral. Morality is not subjective.
Historically, what has been relative is the scope of our moral concerns. When our horizon was the tribe, our concerns were tribal. We often used to kill or enslave outsiders without moral qualms. And some of the facts about human well-being are also relevant for other species, such as the need for food, shelter, health and freedom from harm.
How wide the scope of our moral concerns should be is itself a moral question: who are the others to whom we should do no harm? And it has been widening, though arguably not fast enough. Our vegan descendants may look back in horror at our cruelty to other animals.
When our moral horizon becomes truly and consistently global, when we overcome the delusions and divisiveness of religion, nationalism, racism, sexism, and so on, a long and slow process with many setbacks, we will reach moral maturity. And other species and our environment will be part of the story.