When faced with a decision, each of us is aware that there is a better choice and a worse choice that we could make. Some decisions are a better or worse choice for me alone, for example whether to have milk in coffee. Other decisions impact on others, for example whether to steal another’s wallet or to cheat on my taxes.

So how can we know, or justify, which of our actions or decisions are right or wrong, true or false, permissible or impermissible?

We can probably agree that rightness or wrongness is not vested in some recognisable objective characteristic of an action or decision which labels it right or wrong. Nor is rightness or wrongness simply determined by the customs of the time. No doubt customs may determine what people think is morally good or right, but this is not the same as saying that custom objectively determines what is good or right, since presumably those actions and decisions remain right or wrong, whether or not everyone (or indeed anyone) agrees. Nor can we prove that notions of truth or falsity, permissibility or impermissibility, are bestowed upon actions by God or any other supreme being. Nor is it actually legitimate to make moral decisions based on even a very strongly felt emotion or intuition about what I feel is right or wrong.

Yet having a set of values which guide our behaviour is important. We should be answerable to certain standards of behaviour, and our actions should be able to be judged as right or wrong, good or bad. For some people, their values or beliefs are held strongly enough to justify certain actions, including killing others in the name of their beliefs. Human beings impose values on actions or decisions. Because humans are also intelligent beings, it is reasonable to expect that we can justify the value-set we adhere to, via providing reasons.

As Ronald Dworkin notes, we can prove a chemical reaction is “scientifically true” by a process of repeated observation. However we cannot use the empirical approach of experimentation or repeated observation, to collect moral facts, and so empirically prove it “morally true” that, for example, abortion is right or wrong, in the same way that we can prove it scientifically true that gravity exists. So, compared with the empirical sciences ‘morality is an independent domain of thought’ (Dworkin, 2011, p. 99). That is, moral contentions cannot be subjected to the truth conditions of empirical or scientific experimental proof.

The only way forward if we are to claim validity for our contention, is to provide a substantial, rational, meaningful, and coherent argument in favour of our proposition. So, if I want the right to hold that a contention is true, in a way more than “it is my opinion that …”, then I have to provide arguments in support of that contention. That is, we have a dialogue about it, in order to determine the best action or decision in the circumstances at hand, or to justify the decision made.

We could make appeal to some of the “big” principles of morality – do not kill, do not harm, prevent evil, rescue those in danger, nurture the young, etc – which are by their nature abstract, context-independent and somewhat aspirational. We could make appeal to The Golden Rule and its variations. We could appeal to the traditional ethical frameworks of deontology (torturing a terrorist is always impermissible), teleology (torturing a terrorist may be morally permissible, depending upon the result), or virtue ethics. Whichever approach we might take, the optimum way to translate these principles into the practical reality of our moral decision making, is via coherently articulating our arguments.

This is not simply a solitary reflection or monologue (ethical navel-gazing). We engage in argumentation with one or more others in the moral community who are rational, interested, and are able to understand the principles of moral argumentation. It is only through having a dialogue that we can allow for evaluation of circumstances or context, exceptions to the “rules”, the weighting of different consequences, potentially unique circumstances, and so on.

How may the process of argumentation proceed? Ideally, each participant considers each other ready and willing to understand each other’s argument in support of the moral contention. Thus, they use language in the same way, allow all relevant arguments to be brought to the dialogue, each can question an argument, and there should be no overt or covert compulsion applied by any participant in the argumentative discourse, which itself is rational and impartial. In practice, we cannot legitimately criticise characteristics of another which they did not choose – for example, their skin or hair colour, their ethnicity, and similar characteristics. However, we can legitimately criticise values or beliefs which they choose to adopt – for example, their religion, their politics, their attitudes to gender, and similar.

The aim is to reach consensual agreement via an inclusive and non-coercive rational discourse. A process of argumentation forces on us an active recognition of the viewpoints of others, regardless of our own ethical values. Indeed, such an approach may also reflect a mature society’s acceptance of the responsibility to engage in an active process to determine the validity of normative moral claims and propositions. 

Dworkin, R. (2011). Justice for Hedgehogs (1st ed.). Cambridge Massachusetts: The Belknap Press of Harvard University.