When Oscar Wilde attacked his critics with his definition of selfishness he raised most of the issues which face anyone interested in the question of the ethics of fluoridation of a public water supply.

• 'Selfishness', Wilde suggested, 'is not living as one wishes to live, it is asking other people to live as one wishes to live.'

One principle is sometimes called the principle of beneficence and requires that we act in the best interests of other people. This principle often conflicts with another moral principle of equal importance.

This second principle is sometimes called the principle of autonomy which requires that individuals be permitted to have control over their own lives and destiny so far as is compatible with other people having similar autonomous control over their own lives.

Now in society generally we are used to accepting some diminution in our autonomy for the general good, the possibility of taxation depends on this, as does the control of drugs, the licensing of the sale of alcohol, the regulation of road transport and so on.

However, in medical contexts, perhaps because of the vulnerability of patients or because of a general suspicion of doctors or dentists, great importance is attached to the principle of autonomy. It is, for example, usually considered quite unethical for health professionals to treat people without their consent, or to include them in a clinical trial or even to carry out routine screening, without first making clear what is involved and what side effects might be expected and obtaining formal consent.

Now this principle of autonomy is very powerful indeed, as witness the costs, including social costs that we are often prepared to bear to preserve it. For example, take the case of AIDS and the debate over compulsory or involuntary screening. Our society has so far taken a very strong stand against compulsory screening for AIDS even though such a measure might well protect many people who may be at risk from those who carry HIV and the reason is of course that we value freedom and autonomy very highly.

One question we might want to ask would be is fluoridation more like compulsory screening for AIDS or administering medication without a patient's consent or is it more like taxation or the regulation of road transport? But to ask this sort of question would, I think, be a mistake, for we would be in a sense begging the question of the ethics of fluoridation by trying to assimilate it to models which while analogous, are importantly distinct.

If this is right, then the issue is clear. Those who object to it are in the position of depriving the community of a benefit at no cost to themselves, save that of having their personal preference frustrated. Now to this it might be replied that if personal liberty is to mean anything at all, then the community must be prepared to accept some cost in order to protect it.

After all, the protection of free speech and other civil rights does not come cheap. What the Americans usefully call due process of law, and what we think of here as the administration of justice - the process of providing fair trials and the presumption of innocence in criminal law etc. cost the community dear both in terms of financial resources expended to protect these rights and in terms of the risk to citizens if suspected and probably guilty persons are allowed to run free because there is insufficient evidence against them to secure conviction.

But the right to a fluoride free water supply is not a basic civil right. It is not a right of importance comparable to free speech, freedom of assembly, or equal protection before the law. It is not a right which is needed in order to secure an individual's entitlement to the protection of his human dignity and standing as a citizen, or to protect his entitlement to the same concern and respect as is accorded any other citizen. Neither is it a right required in order to secure access to the political process, or in order to prevent injustice or one which affects an individual's ability to make autonomous choices or to pursue her own chosen goals or objectives in her own way.

In short, not all constraints on free choice are constraints on liberty. The good citizens of Hartlepool are not less free than those of Manchester because they have naturally occurring fluoride in their water supply. They do not have fewer civil rights in consequence than do the people of Wigan. Indeed, if this were so, if they did have fewer civil rights it would be a major priority to remove the naturally occurring fluoride from the water supply of Hartlepool or to provide them with alternative sources of water

There is of course also an important resources dimension to the problem. In circumstances in which we have to face permanently scarce resources and moreover one in which scarcity of resources means that people are dying and will continue to die for want of the help and treatment that resources could purchase, we have an added ethical responsibility to take those measures available to us which will enable us to provide the maximum possible level of health care. If, as evidence emphatically suggests, fluoridation would significantly reduce dental caries then the resources saved could make a dramatic impact on other aspects of dental or health care more generally.

In considering the ethics of fluoridation one might legitimately reverse the question and ask if fellow citizens are entitled to impose, not only a disadvantage on the community at large, but impose actual deaths and the risk of death on children for the sake of a minor diminution in the range of choices available? We should ask not are we entitled to impose fluoridation on unwilling people but are the unwilling people entitled to impose the risks, damage and costs of failure to fluoridate on the community at large. When we compare the freedoms at stake, the most crucial is surely the one which involves liberation from pain and disease.

To take one example only, in the course of their dental care, 32000 general anaesthetics were provided in the North Western Health Region to children under ten in 1985 alone, and in the five years to 1988 at least four children in the region have died under anaesthetic.2