I think, therefore, that my earlier conclusion is still justified: we have adequate evidence that schizophrenia and manic-depressive illness, and also some sexual disorders and some forms of drug dependence, carry with them an intrinsic biological disadvantage, and on these grounds are justifiably regarded as illness; but it is not yet clear whether the same is true of neurotic illness and the ill-defined territory of personality disorder.
What is the significance of this conclusion? First, it is an answer to the argument that there is no such thing as mental illness. At least part of the territory regarded by psychiatrists as mental illness fulfils the same criteria as those required for physical illness. But only part of it does so. Many of the conditions which psychiatrists have come to regard as illness, and hence as requiring treatment, do not qualify, or rather there is little evidence at present that they do. This does not necessarily mean that psychiatrists have no right to meddle in these areas, or that people who are anxious or depressed should be dissuaded from visiting their doctors. For one thing, childbirth and family planning provide precedents for the involvement of medicine beyond the boundaries of disease.
Even so, psychiatrists might be well advised to reconsider where their sphere of responsibility should end. A century ago they were concerned only with madness. But from that time onwards their concept of their proper role expanded steadily until the stage was reached, particularly in North America, at which some were claiming a mandate—and the ability—to treat anyone who was unhappy for whatever reason, and anyone whose behaviour was annoying or alarming to other people. It is worth reflecting whether the many attempts we have recently witnessed to discredit the concept of mental illness might not be a reaction to the equally absurd claims we have made that all unhappiness and all undesirable behaviour are manifestations of mental illness.
The attempt to relieve suffering is medicine's oldest and noblest tradition, and I am not suggesting that psychiatrists should stop trying to help husbands and wives to live together in harmony, or aimless adolescents to find their feet. But if we are to venture into such areas let it be in full recognition of the fact that in doing so we may be straying outside our proper boundary, and that in the end it may turn out that other people can deal with such problems as well as or better than we can, and that in these areas their training and their concepts are more appropriate than ours. By all means let us insist that schizophrenia is an illness and that we are better equipped to understand and treat it than anyone else. But let us not try to do the same for all the woes of mankind.