Meta ethics is the study of the issues that underpin all ethical discussions. What is the nature of ethical language? What do the words "good", "bad", "right" or "wrong" really mean? Are human beings free and responsible? What is a human being? Who counts as a person and who does not? What is the difference between a human being and any other animal? Is moral status dependent on DNA, on rationality, socialisation – or something else? All of these are matters of meta ethics.

Ethical language is beset by many of the same problems as religious language. This topic is given fuller treatment in the Philosophy section of this site under Language. Statements including claims about goodness, badness, rightness and wrongness are basically unverifiable. There is no empirical test to back up such claims, no probe whose readings will confirm that "murder is wrong", for example.

Plato and Aristotle

From the earliest times philosophers have sought to define goodness to support claims concerning it. Plato offered a metaphysical definition of goodness as a reflection of a mysterious "the form of the good", which exists beyond time and space in the realm of ideas and which we recognise in some things and actions but not in others, by bringing the assessment of goodness firmly within the realm of human experience. Aristotle reacted against the ambiguity of this. For him, goodness came in the degree to which something fulfils its nature. Aristotle saw that our understanding of the nature or form of things starts with our experience of them. For example, we might see a lot of trees, learn about them and become knowledgeable about what they should be like, and this enables us to judge some trees as better than others in terms of how well an individual specimen measures up to what a tree could and should be in our experience. Judgement is a rational process but it is based on categories which are derived from direct experience - Aristotle's approach does not rely on human beings having any mysterious understanding of metaphysical truths as Plato's did.

For Aristotle, reason dictates that a thing's nature is made up of four causes - its material, efficient, formal and final causes.

a. Material causes are the basic ingredients that make it up.
b. Efficient causes are the agents and accidents that bring it into being.
c. A thing's formal cause is what makes it what it is, its recipe or nature.
d. A thing's final cause is its purpose, what it aims towards.

Take an oak tree. Material causes would include carbon, oxygen etc. Efficient causes would include acorn, earth, sun and rain. The formal cause would be the oak's DNA (as opposed to that of elm, ash or wombat) and the final cause would be growing, reproducing and so on.

Aristotle argued that a good object fulfils its formal cause – i.e. it is a good example of what it is - and so achieves its final cause to the best degree. Basically, for Aristotle, goodness lies in flourishing. A "good" oak tree grows very tall, produces many acorns from which new saplings grow, and so on. Conversely an "evil" oak tree ("evil" naturally, rather than morally, because the oak is a non-free and thus non-moral being) would be small, infertile and generally functioning poorly.

This applies to human beings as well as to all other things. A good human being is fully human, continues to live, grow, reproduce and otherwise flourish. An evil human being, either naturally or morally, fails to fulfil their humanity and falls short by living a short, poor, barren and insignificant life. This is the basis of Aristotelian natural law and has been used as the foundation of naturalistic ethics from Aquinas to Grisez and Finnis.

Applying Aristotle's definition to humans

Using Aristotle's definition of goodness would yield some grounds for claiming that something was good or that something else was better than it. Yet the criteria for making these judgements are arguably subjective. Can we really and conclusively define human nature? In the eighteenth century Hutcheson, Bentham and others looked for a simpler basis for making claims about good, bad, right and wrong. Building on Locke, Hume had argued that these judgements are simply expressions of opinion or emotion, and so had opened up the road towards radical relativism, postmodernism and the dominant emotivism of the twentieth century.

To utilitarianism

Bentham was not satisfied to accept Hume's argument, however. He observed that "nature has placed mankind under two sovereign masters: the pursuit of pleasure and the avoidance of pain". For Bentham, who first coined the term "utilitarianism", it was simply a matter of common sense to judge that good actions produced "the greatest happiness for the greatest number" and that bad actions produced pain.

Utilitarianism is one remedy against the problems with ethical language, though arguably it is just as difficult to define and measure pleasure and pain as it is to define and measure a broader concept of goodness. Nevertheless, utilitarianism had an air of scientific credibility and survives as a major school of ethics and one enduringly popular with politicians, lawyers and scientists for its ability to provide apparently verifiable data to support claims such as "murder is wrong".

Limitations of utilitarianism

However even from the earliest days utilitarianism has attracted harsh criticism. John Stuart Mill, Bentham's godson, argued that Bentham's understanding of pleasure was deficient and that the whole system was beset by the problem of prediction, that is, of accurately predicting the outcomes of actions, and of being influenced by self-interest. Immanuel Kant would have agreed with much of Mill's argument.

Kant's own approach to ethics rejected the simplistic notion that we are driven by raw pleasure and the avoidance of pain, as much as it rejected the traditional prescriptive definition of human nature and flourishing that had been handed down from Aristotle and the Church. Instead he argued that human nature lies in being rational and free and that we flourish when we act on principle and freely for principle's sake consistently.

Immanuel Kant's definition of human nature and goodness gets us no further towards a defence of the meaningfulness of statements relating to good, bad, right and wrong. There is no scientific tool to measure the rationality of the maxim of somebody's action, nor to measure the freedom or motivation of their will when they determined on the action. Kant claims that there is a single rational principle behind all good actions and that, though this principle would be known synthetically from experience, the goodness of maxims would be known analytically, by their logical relationship with the single categorical imperative.

Ayer's emotivist criticism of Kant

Among those who take issue with Kant's claims are those known as emotivists, such as AJ Ayer, who believe that moral statements are not objective but merely express the speaker's feelings. At the beginning of the twentieth century, developments in the philosophy of language led philosophers to class all statements which were not physically, empirically verifiable as essentially meaningless. This approach assumes that the only consistent point of reference for language is sensory experience and that any statement that does not refer to it can only be relative to the opinions or ideas of an individual.

This relativist approach cuts away the possibility of value judgements. Ethics, for the relativist, begins with meta ethics and then becomes simply an anthropological study, describing how people do behave, almost with a sense of incredulity, rather than trying to build logical foundations for judgements or prescribing how people should behave.

Emotivists would dispute Kant's idea that the principle of goodness may be known on the basis of experience - and therefore the rest of his ethics becomes redundant. Ayer does not just dispute the foundations for Kant's ethics; he disputes the foundations of any statement which contains claims about "emotive" terms such as good, bad, right or wrong.

A common absolutism

The relativist labels many other approaches to ethics "absolutist", a term which seems pejorative and carries connotations of being bigoted, refusing to engage with the facts, inflexible and not interested in individual people or situations. Natural law and Kantian ethics are often called "absolutist" but in reality the same sort of reasoning underpins rule utilitarianism and virtue ethics. Any system which defines terms such as "good" and "right" and which claims a common point of reference for these terms will have a consistent attitude to actions such as murder and theft, classing them as wrong for everybody in most situations (except possibly when they are the lesser of two evils). This contrasts with the relativist approach, which would see that any action could be right or wrong for some individuals or in some situations, there being nothing fundamentally good or bad about the action, only a general sense of approbation or disapprobation.