The Pointlessness of moral non-realism

The moral non-realist argument, which claims there is no objective or mind-independent 'good' or 'bad' is powerful, albeit in a nihilistic manner.

Typically in philosophy, whenever something is debated, philosophers agree on a series of assumptions that frame the debate. In ethics, with which this post concerns itself, a crucial assumption is that of moral realism, i.e. that some things are objectively good and some things are objectively bad. In the utilitarian framework, for example, pleasure is good whilst pain is bad.

The use of such unprovable or unverifiable assumptions leaves moral realists open to a perfectly legitimate criticism of the arbitrariness of selecting an assumption. This objection has little to no practical impact as it has never and probably will never lead to humans abandoning pursuit of the definition of goodness, and the favouring of certain moral claims over others. To those interested in philosophy, however, it seems to be yet another instance of scepticism providing a frustratingly nihilistic yet legitimate counterargument that relegates all moral statements to opinion.

The counter-argument that I will now present aims not to conclusively prove that there is an objective morality but simply that, so long as there is a non-zero probability of there being an objective morality, all human beings and philosophers should behave as though there is one. This way, moral non-realism is relegated to being an amusing and irrelevant thought experiment.

Systems of logic imply that the probability of a particular state of affairs is a decreasing function of the number of unprovable/unverifiable assumptions (that also cannot be disproved) used to attempt to prove that state of affairs. This is why Descartes can say with absolute certainty 'cogito ero Sum'; his proof that consciousness exists is based on zero assumptions.

In order to understand this, imagine a theory based on 0 unprovable or unverifiable assumptions. Using only provable assumptions, an individual can deduce a conclusion A. 'A' is therefore true with 100% probability as it follows logically from assumptions that are true with 100% probability; there is no space for probability to be reduced.

Before I explain how this related to moral realism, I will quickly clarify what types of assumption are allowed. Under the conditions I have outlined so far, it may seem like a very specific statement such as 'an elephant exists' could be proved by using only one assumption, for example 'there is such a thing as an elephant and it exists'. The reason why this is not allowed is because without, for example, an assumption regarding the nature of matter and the inductive processes that all empirical research relies on, any physical facts regarding the elephant's existence would not exist. The elephant would be non-physical and therefore not what we understand an elephant to be.

Now onto how this applies to moral realism. Let's model the moral non-realist position as one where their view of the world (which is not the same as that of the absolute skeptic i.e. they believe that human beings exist, the world exists, and that various other facts are true - they differ simply by believing that there are no 'moral facts'; there is no objective definition of 'good' or 'bad') is based on x number of unprovable assumptions. There will be x-1 unprovable assumptions relating to various facts concerning the physical world, the human mind and so on, and then one unprovable assumption that states moral facts do not exist. By contrast, the moral realist argument has the same x-1 assumptions and then one assumption that moral facts do exist (by only differing in one assumption, we are controlling for all other assumptions, thus allowing us to isolate the differences in the moral realist and non-realist positions).

It is important to note that the moral non-realist argument cannot be modelled by just using the x-1 assumptions. This is because the opposite of a statement is its negation, not its absence. In the absence of either the realist or non-realist assumptions, we would live in a universe where neither obtained, not  in one where moral non-realism obtained. For moral non-realism to 'exist', we need its assumption; without the assumption, nothing relating to morality exists.

So we now have one universe where moral realism exists and one where it does not exist. We do not know what the probabilities of these two universes are, but we do know that they are equal (they do not necessarily sum to 1 however - this is why we do not know their exact probability).

Ok, now let's bring the discussion back to the initial claim I promised I would make; to demonstrate that, regardless of whether moral realism is true or not, people and philosophers should always behave as though it is true.

This part is actually very simple. In the moral non-realist universe, no objective good or bad exists. The claim isn't that there is no social good or social bad, but that there is no good or bad of any kind. People might make decisions on the basis of things they find more fun, or things that they prefer, but this in no way correlates with what is morally superior. This means that, in such a world, imposing one set of actions, even one as [for us] absurd as killing all ginger people, would not lead to a morally worse situation. For it to do so, moral non-realists would have to assign a superior moral value to liberty, or autonomy, or the ability to have fun, or whatever. To do this would contradict the definition of moral non-realism. As such, one could not say that imposing a system of ethics upon this world 'ought' not to happen. 'Ought' statements carry no truth-value in a moral non-realist world, or at least no truth-value that corresponds to some objective, mind-independent conception of good or bad.

Now, any being alive on our everyday planet earth does not know whether the world is morally realist or non-realist; they do not know this because they cannot prove that either is true or untrue. However, as explained above, they can know what the probability of the world being morally realist versus being morally non-realist is.

So we now live in a universe where moral realism is true with probability p and moral non-realism is also true with probability p. In the universe where moral non-realism is true, the universe is no worse off imposing a system of ethics than it is not imposing one. In the moral-realist one, there is obviously a benefit or good in imposing a system of ethics.

Thus the moral non-realist argument is self-defeating. So long as there is a non-zero probability of moral realism being true, and there is no good reason to believe that human attempts to identify and enforce the objective good will be more bad than good, humans should always try to identify and enforce what is good.

Note; I am aware that there may be some possible problems with the probabilities that I assigned to moral realism and non-realism, but this does not detract from the key point which is that there is definitely a non-zero probability of moral realism being true.