I mostly live in an attic in Oxford,

so you'll forgive me for being completely outside my environment tonight.

I'm afraid I'm not going to be terribly

funny like the previous speakers.

That's partly because psychiatrists aren't very funny people.

Freud famously said that there's no such thing as a joke.

But, no, actually it's because that

my topic tonight doesn't lend itself very well to jokes

and my topic is actually a very serious topic.

It's depression.

Now, most people think of depression

as a mental disorder that is a biological illness of the brain.

Today, I'm going to argue that the concept of depression

as a mental disorder has been over extended,

has been unhelpfully over extended to

include all manner of human suffering.

And, more controversially,

that depression or "depression" as broadly understood,

can actually be good for us,

an idea that I explored, that I developed

in my recent book "The Meaning of Madness."

Now let us begin by thinking very broadly about depression.

There are important geographical variations

in the prevalence of depression.

And these can in large part be accounted for

by socio-cultural rather than biological factors.

In traditional societies, human distress is more likely to be seen

as an indicator of the need to address important life problems

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 with which to talk or think about depression.

And many people in traditional societies

with what may be construed as depression

present instead with physical symptoms,

such as fatigue, or headache, or chest pain.

So, for example, Punjabi women,

who have recently emigrated to the United Kingdom

and given birth find it baffling

that a health visitor should pop around

to make sure that they haven't developed post-natal depression.

I mean, not only had they never

conceived of giving birth as anything but a joyous event

but they don't even have a word

with which to translate the concept of depression into Punjabi.

Now, in modern societies such as the UK and the USA,

people talk about depression very freely,

very readily, very openly.

As a result, they are far more likely to interpret

their distress in terms of depression

and also far more likely to seek out a diagnosis of the illness.

At the same time, groups with vested interests,

such as pharmaceutical companies

or indeed, so called mental health experts

promote the notion of "saccharin happiness" as a natural,

default state and of human misery, of human distress

as a mental disorder.

The concept of depression as a mental disorder can be useful

for some of the more severe intractible cases

that are treated by hospital psychiatrists.

But probably not for the vast majority of cases

which are relatively mild and short-lived

and easily understood in terms of life problems,

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 themselves

which have become increasingly individualistic

and divorced from traditional values.

For many people living in our society today,

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 a mental disorder

our society may be subtly implying

that the problem lies not with itself, but with them,

fragile and failing individuals that they are.

Now, of course, many people prefer to buy into this

reductionist, physicalist explanation

rather than, I suppose, confront their existential angst.

However, thinking of human distress in terms of

a mental disorder can be counterproductive

because it can prevent people from identifying

and addressing the important psychological

or life problems that are at the root of their distress.

Now, all of this is not to say that

the concept of depression

as a mental disorder is bogus,

not at all,

but only that the diagnosis of depression

has been overextended

to include far more than just depression,

the mental disorder.

If like the majority of medical conditions

depression could be diagnosed according to its etiology

or pathology, that is, according to its cause or effect,

then such a situation, such a problem

would never have arisen.

Unfortunately, depression cannot as yet be diagnosed

according ot its etiology or pathology

but only according to its clinical manifestations or symptoms.

Given this, a doctor cannot base a diagnosis

of depression on anything so objective as for example

a blood test as in malaria,

or a brain scan as in stroke

but only on his subjective interpretation

of the nature and severity of the patient's symptoms.

If some of these symptoms happen to tally with

a diagnostic criteria for depression,

then, you know, bingo, the doctor is justified

in making a diagnosis of depression.

Now, the problem here

is that the definition of depression is circular,

the concept of depression

is based on the symptoms of depression,

and the symptoms of depression, in turn,

are based on the concept of depression.

Thus, it is impossible to be certain

that the concept of depression

maps onto any distinct disease entity.

And, particularly since a diagnosis of depression

can apply to anything from mild depression to depressive psychosis,

and depressive stupor

and overlap with a number of other mental disorders,

including anxiety disorders, dysthymia,

and adjustment disorder.

One of the consequences of our many of symptoms approach

to diagnosing depression is that two people

with absolutely no symptoms in common,

not even depressed moods,

can both end up with the same diagnosis of depression.

For this reason especially

the concept of depression has been attacked

for being little more than a socially constructed dustbin

for all manner of human suffering.

Now, let us grant, as the orthodoxy has it

that every person inherits a certain

compliment of genes that make him or her

more or less vulnerable to developing depression

or a state that might be diagnosed as depression

during his or her lifetime.

And let us also begin to refer

to this state rather than depression

as the depressive position

to include both clinical depression

and milder forms of depressed moods.

A person enters the depressive position if the amount of stress

that he comes under is greater than

the amount of stress that he can tolerate

given the compliment of genes that he has inherited.

Now, genes for potentially debilitating disorders

such as depression tend to pass out of a population

over time, over a very, very long period of time -

we're talking hundreds of generations -

because affected people have fewer children

or fewer healthy children than non-affected people.

The fact that this has not happened for this - depression -

suggests that the genes are being selected for

despite their potentially debilitating effects

in a significant proportion of the population

and therefore that these genes

must be conferring some important adaptive advantage.

Now, before talking about what important adaptive advantage

these genes could be conferring

I think it's important to note that there are other instances of genes

that both predispose to an illness and confer

an important adaptive advantage

and the most quoted or most studied example is usually

I would say sickle cell disease.

In sickle cell disease, red blood cells assume a rigid sickle cell

that restricts their passage through narrow blood vessels.

This leads to a number of serious physical complications,

and in traditional or historical societies

to a radically curtailed life expectancy.

At the same time, however,

carrying just one allele of the sickle cell gene

prevents malarial parasites

from reproducing in red blood cells,

and thereby confers immunity to malaria.

The fact that the genes for sickle cell disease

are particularly common in populations from malarial regions suggests

that at least in evolutionary terms,

a debilitating illness in the few can be a price worth paying

for an important adaptive advantage in the many.

Now, what important adaptive advantage

could the depressive position be conferring?

Now if I've made you fall asleep, I hope I haven't,

but If I have made you fall asleep then please wake up now

because I think this is going to be the most interesting part of my talk.

So what important adaptive advantage

can the depressive position be conferring?

Just as physical pain has evolved to signal injury

and to prevent further injury,

so the depressive position may have evolved

to remove us from damaging, distressing, or futile situations.

The time and space and solitude

that the adoption of a depressive position 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 meaningful to us

and relate to them more meaningfully

and with greater compassion.

In other words, the depressive position may have evolved

as a signal that something is seriously wrong

and needs working through and changing

or at least processing and understanding.

Sometimes we can become so immersed

in the humdrum of our everyday lives

that we no longer have time to think and feel about ourselves

and so lose sight of our bigger picture.

The adoption of the depressive position

can force us to cast off the Pollyannish optimism

and rose-tinted spectacles that shield us from reality;

to take a step back,

to reevaluate our priorities,

and to formulate a realistic or the modest plan for fulfilling them.

Now although the adoption of the depressive position

can fulfill what I would unfortunately call

such a mundane purpose,

it can also enable us to develop a more refined perspective

and deeper understanding of ourselves,

of our lives, and of life in general.

From an existential stand point,

the adoption of the depressive position

obliges us to become aware of our mortality and freedom

and challenges us to exercise the latter

within the framework of the former.

By meeting this difficult challenge,

we are able to break out of the mold

that has been imposed upon us,

discover who we truly are,

and in so doing, begin to give deep meaning to our lives.

Many of the most creative and insightful people in our society

suffer or suffered from depression

or a state that may or would have been diagnosed as depression.

They include the politicians Winston Churchill and Abraham Lincoln.

The poets, Charles Baudelaire, Elizabeth Bishop,

Hart Crane, Emily Dickinson, 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 Green, Leo Tolstoy, Evelyn Waugh

and Tennesee Williams

and the list just goes on and on and on.

To quote Marcel Proust,

who himself suffered from very severe depression,

"Happiness is good for the body,