Hugh McLachlan: Why Labour's election slogan is far from fair

It might seem that fairness is something we can all agree on, all aim for and all have. However, this is not so. "Fairness" is a contentious notion and an unreliable policy aim.

Fairness can be contrasted with justice. Justice should be considered with reference to rights. Rights should be considered in relation to duties. For instance, your fate is unfair if, on the way to an important job interview, you are struck by lightning or accidentally tripped by a pedestrian. If, in the same circumstances, you are struck by a mugger, your fate is both unfair and unjust. The mugger infringes your right not to be assaulted and breaches his duty not to assault you.

The term "fairness" is, like "beauty" and "humour", indefinable. We can give examples of particular things that we consider to be fair, humorous or beautiful but that is quite different from giving a definition of the words "fair", "humorous" or "beautiful". Different people consider different things to be fair. Furthermore, the same person can consider the same thing to be fair or unfair depending on the point of view it is considered from. Moreover, to treat one particular person fairly might involve treating others unfairly.

In some contexts, fairness is crucially important. In others, it is not. With some things, if we cannot do them fairly, we should not do them at all. For instance, if we cannot give someone a fair trial, we should not give him a trial. However, if we cannot devise, for instance, a fair system of taxation or a fair system of voting in parliamentary elections, we must still levy taxes and arrange elections in the meantime.

It might well be unfair to alleged victims if some particular people are not put on trial because they could not be tried fairly. However, if they are tried fairly, the procedures and their outcomes might well be unfair to the alleged victims and to other people. Fairness for all is not readily attainable.

Notice how the laudable attempts to try to ensure that, if he is put on trial again, Jon Venables will be tried fairly are considered by many people to be, from various ways of looking at the matter, grossly unfair. For instance, is the anonymity given to him fair to other men of his age who are put on trial for alleged sex offences and might be imagined by members of the jury to be Jon Venables?

Many people argue it is fair that people who do the same job equally well should be paid the same by their employers for doing so and that people who do more or better work should be paid more. In Matthew's gospel, Chapter 20, verses 1-16, the parable of the labourers in the vineyard illustrates some of the complexities involved with this application of the idea of fairness.

The owner of a vineyard hired labourers to work for a day for an agreed fee. Later in the day, at different times, he hired other labourers to work for the remainder of the day. When they were paid, all were paid the same, no matter how long they had worked. There were understandable complaints from those who worked longer that this was unfair.

On the other hand, it can be argued that, since they agreed to work for the wage they were paid, they were treated fairly. It could be said that the owner of the vineyard treated all the labourers fairly, even if he treated some of them more generously than others. In any case, is it not fair that the owner is permitted to run his own business in his own way? Some but not all people would think so.

We all benefit from the existence of the state and we are all, as citizens, considered to be equals. For instance, we all have one and only one vote in parliamentary elections. Should we not all bear an equal burden of taxation? There is a case for saying that the fairest sort of taxation is a poll tax, where all citizens pay the same amount in absolute terms. However, we know from experience that poll taxes are impractical because they are difficult to collect. Rightly or wrongly, they are also commonly felt to be unfair.

Sir Paul McCartney, like many rich people, draws little from and contributes a vast amount to the public purse. He has already paid, one might think, more than enough in taxation. Nonetheless, if, instead of enjoying his ease, he gives yet another public performance, for every pound he earns, the state will take 40p from him. This strikes me as very unfair.

Within our system of parliamentary democracy, two of our cherished conventions are "one citizen, one vote" and – within parliament – "one MP, one vote". Although such conventions are very difficult to defend as abstract principles, they are generally considered to be particularly fair. However, they lead to paradoxes and to what are often thought of as unfair implications and consequences.

MPs in constituencies with few trees and no oil can still vote on issues such as forestry and fuel policy. MPs who have Scottish constituencies are able to vote on matters that relate directly only to England or parts of it, whereas MPs who have English constituencies do not have a similar say over Scottish affairs. Some people get distressed by such paradoxes and consider them unfair. However paradoxes of one sort or another cannot be eradicated completely without eradicating the parliamentary system, which we hold to be a fair one.

In our system, those who are not adults are not given a vote in parliamentary elections, while all citizens are given one, and only one, vote each. This hardly seems fair, although it is difficult to imagine how a fairer system could be practical. What do adults have that children and youths lack which is relevant to the allocation of a vote? Is it knowledge? Is it experience? Is it soundness of judgment? Is it intelligence? It is difficult to think of a feature that warrants giving adult citizens the vote and which adult citizens share equally. It might well be fairer if some non-adults had a vote and some adults had several, while others had none.

"Fairness" is a dubious political ideal. It is far from clear that fairness for all is a feasible aim. Even if we could agree on what would constitute a totally fair society, it is not obvious that politicians could fairly bring it about, nor that many of us would want to live in it.

Hugh V McLachlan is professor of applied philosophy at the School of Law and Social Sciences at Glasgow Caledonian University.