This crayon drawing by a hospital in-patient with severe depression alludes to her temporary withdrawal from mainstream society. The months that she spent in hospital gave her the time and the solitude to think over her life, and the motivation to make difficult but necessary changes to it. She went on to make a full recovery.

Many a man curses the rain that falls upon his head, and knows not that it brings abundance to drive away the hunger. – St Basil the Great

Happiness is good for the body, but it is grief which develops the strengths of the mind. – Marcel Proust

Depression around the world

There are important geographical variations in the prevalence of depression, and these can in large part be accounted for by socio-cultural factors. In traditional societies, human distress is more likely to be seen as an indicator of the need to address important life problems, rather than as a mental disorder requiring professional treatment. For this reason, the diagnosis of depression is correspondingly less common. Some linguistic communities do not have a word or even a concept for ‘depression’, and many people from traditional societies with what may be construed as depression present with physical complaints such as headache or chest pain rather than with psychological complaints. Punjabi women who have recently immigrated to the UK and given birth find it baffling that a health visitor should pop round to ask them if they are depressed. Not only had they never considered the possibility that giving birth could be anything other than a joyous event, but they do not even have a word with which to translate the concept of ‘depression’ into Punjabi!

In modern societies such as the UK and the USA, people talk about depression more readily and more openly. As a result, they are more likely to interpret their distress in terms of depression, and less likely to fear being stigmatised if they seek out a diagnosis of the illness. At the same time, groups with vested interests such as pharmaceutical companies and mental health experts promote the notion of saccharine happiness as a natural, default state, and of human distress as a mental disorder. The concept of depression as a mental disorder may be useful for the more severe and intractable cases treated by hospital psychiatrists, but probably not for the majority of cases, which, for the most part, are mild and short-lived, and easily interpreted in terms of life circumstances, human nature, or the human condition.

Another (non-mutually exclusive) explanation for the important geographical variations in the prevalence of depression may lie in the nature of modern societies, which have become increasingly individualistic and divorced from traditional values. For many people living in our society, life can seem both suffocating and far removed, lonely even and especially amongst the multitudes, and not only meaningless but absurd. By encoding their distress in terms of mental disorder, our society may be subtly implying that the problem lies not with itself, but with them. However, thinking of the milder forms of depression in terms of an illness can be counterproductive, as it can prevent people from identifying and addressing the important life problems that are at the root of their distress.

Problems with diagnosis

All this is not to say that the concept of depression as a mental disorder is bogus, but only that the diagnosis of depression may have been over-extended to include far more than just depression the mental disorder. If, like the majority of medical conditions, depression could be defined and diagnosed according to its aetiology or pathology, such a state of affairs could not have arisen. Unfortunately, depression cannot as yet be defined according to its aetiology or pathology, but only according to its clinical manifestations and symptoms. For this reason, a doctor cannot base a diagnosis of depression on any objective criterion such as a blood test or a brain scan, but only on his subjective interpretation of the nature and severity of the patient’s symptoms. If some of these symptoms appear to tally with the diagnostic criteria for depression, then the doctor is able to justify making a diagnosis of depression.

One important problem here is that the definition of ‘depression’ is circular: the concept of depression is defined according to the symptoms of depression, which are in turn defined according to the concept of depression. Thus, it is impossible to be certain that the concept of depression maps onto any distinct disease entity, particularly since a diagnosis of depression can apply to anything from mild depression to depressive psychosis and depressive stupor, and overlap with several other categories of mental disorder including dysthymia, adjustment disorders, and anxiety disorders. Indeed, one of the consequences of the ‘menu of symptoms’ approach to diagnosing depression is that two people with absolutely no symptoms in common can both end up with the same diagnosis of depression. For this reason especially, the concept of depression has been charged with being little more than a socially constructed dustbin for all manner of human suffering.

An adaptive role?

Every person inherits a certain complement of genes that make her more or less vulnerable to developing depression during her lifetime. A person suffers from depression if the amount of stress that she comes under is greater than the amount of stress that she can tolerate, given her vulnerability to developing depression. Genes for potentially debilitating disorders such as depression usually pass out of a population over time because affected people have, on average, fewer children than non-affected people. The fact that this has not happened for depression suggests that the responsible genes are being maintained despite their potentially debilitating effects on a significant proportion of the population, and thus that they are lending an important adaptive or evolutionary advantage.

There are other instances of genes that both predispose to an illness and lend an important adaptive advantage. In sickle cell disease, for example, red blood cells assume a rigid sickle shape that restricts their passage through tiny blood vessels. This leads to a number of serious physical complications and, in traditional societies, to a radically shortened life expectancy. At the same time, carrying just one allele of the sickle cell gene (‘sickle cell trait’) makes it impossible for malarial parasites to reproduce inside red blood cells, and so confers immunity to malaria. The fact that the gene for sickle cell anaemia is particularly common in populations from malarial regions suggests that, in evolutionary terms, a debilitating illness in the few can be a price worth paying for an important adaptive advantage in the many.

What important adaptive advantage could depression have? Just as physical pain has evolved to signal injury and to prevent further injury, so depression may have evolved to remove us from distressing, damaging, or futile situations. The time and space and solitude that depression affords prevents us from making rash decisions, enables us to see the bigger picture, and – in the context of being a social animal – to reassess our social relationships, think about those who are significant to us, and relate to them more meaningfully and with greater understanding. Thus, depression may have evolved as a signal that something is seriously wrong and needs working through and changing or, at least, understanding. Sometimes people can become so immersed in the humdrum of their everyday lives that they no longer have the time to think and feel about themselves, and so lose sight of their bigger picture. The experience of depression can force them to stand back at a distance, re-evaluate and prioritise their needs, and formulate a modest but realistic plan for fulfilling them.

Sorrow’s children

Although the experience of depression can serve such a mundane purpose, it can also enable a person to develop a more refined perspective and deeper understanding of her life and of life in general. From an existential standpoint, the experience of depression obliges the person to become aware of her mortality and freedom, and challenges her to exercise the latter within the framework of the former. By meeting this difficult challenge, the person is able to break out of the mould that has been imposed upon her, discover who she truly is, and, in so doing, begin to give deep meaning to her life. Indeed, many of the most creative and most insightful people in society suffer or suffered from depression. They include the politicians Winston Churchill and Abraham Lincoln; the poets Charles Baudelaire, Hart Crane, Sylvia Plath, and Rainer Maria Rilke; the thinkers Michel Foucault, William James, John Stuart Mill, Isaac Newton, Friedrich Nietzsche, and Arthur Schopenhauer; and the writers Charles Dickens, William Faulkner, Graham Greene, Leo Tolstoy, Evelyn Waugh, Tennessee Williams, and many, many others.

The curse of the strong

People with depression are often stigmatised as ‘failures’ or ‘losers’. Of course, nothing could be further from the truth. If anything, the sorts of people who are most vulnerable to developing depression are all the opposite of failures or losers. If they are suffering from depression, it is most probably because they have tried too hard or taken on too much, so hard and so much that they have made themselves ill with depression. In other words, if they are suffering from depression, it is because their world was simply not good enough for them. They wanted more, they wanted better, and they wanted different, not just for themselves, but for all those around them. So if they are failures or losers, this is only because they set the bar far too high. They could have swept everything under the carpet and pretended, as many people do, that all is for the best in the best of possible worlds. However, unlike many people, they had the honesty and the strength to admit that something was amiss, that something was not quite right. So rather than being failures or losers, they are just the opposite: they are ambitious, truthful, and courageous. And that is precisely why they got ill. Getting ill is never a good thing, but in the case of depression it can present a precious opportunity to identify and to address some very challenging life problems, and to develop a deeper and more refined understanding and appreciation of one’s life and of life in general.

A note of caution

Depression should not be romanticised, sought out, or left unattended simply because it may or may not predispose to problem-solving, personal development, or creativity. The most severe forms of depression have a strong biological basis and are not related to a person’s life circumstances or aspirations. All forms of depression are drab and intensely painful, and most people who suffer from depression would never wish it on anyone, least of all themselves. In some cases, depression can lead to serious injury or even to death through accident, self-neglect, or self-harm. Even highly successful people who suffered from depression such as Hart Crane and Sylvia Plath ended up committing suicide in the end, and most people who attempt suicide do so because they are suffering with some form of depression.