At the time of the tragic death in 1997 of Princess Diana, many newspapers and other media outlets stated that “Britain is having a collective nervous breakdown.” This paper will consider whether it is possible to have a nervous breakdown (to use popular terminology), or any other disorder, in a collectivity.

A fundamental part in the diagnosis of a mental disorder in an individual is the mental state examination, with the careful observation of the following criteria: general appearance and behavior, speech, affect and mood, quality, range, appropriateness, depersonalisation and de-realisation, thought (stream, form and content), perception, cognition, judgement, insight and rapport [1]. As stated in the DSM-5 a case formulation of a patient must involve a careful clinical history and consideration of the social, psychological and biological factors that may have contributed to developing a given mental disorder [2]. This paper considers both the social and psychological factors that may have contributed to the onset of a collective mental state.

The existence of a consciousness or mental state possessed by a group, crowd, community or whole society (a collectivity), over and above the sum of individual consciousnesses has long been asserted. Lebon [3] observed that in crowds a collective mind emerged, a discussion ensued. Freud [4] accepted the concept of the group mind but considered that Lebon [3] had underestimated the role of leadership. Durkheim discussed in depth the concept of the collective consciousness [5] and Halbwachs introduced the concept of the collective memory [6].

However, there is also a long-established denial that collective mental states exist. This is the concept of Methodological Individualism which holds that all behavior must be reduced to the behavior and actions of individuals, a view associated with Schumpeter, Popper and many other theorists [7]. The philosophical nature of genuinely collective emotions cannot be proven or disproven, but there is considerable support for acceptance of them [8]. The methodological problem of how a collective entity could be tested empirically has had the effect of placing it outside of modern empirical social science, which is predominantly quantitative.

The psychiatric literature reflects this controversy. Folie à deux has been recognised since 1877 as a condition passed by contagion as a induced psychotic disorder between two people such as siblings or spouses. However, in the most recent Diagnostic and Statistical Manual of Mental Disorders (DSM-5) [2], the Shared Psychotic Disorder (Folie à Deux) is not considered as a separate entity, leaving the diagnostician to classify the secondary patient as “Delusional Disorder” or Other Specified Schizophrenic Spectrum and Other Psychotic Disorder”.

One interesting example of shared disorder was reported to have occurred in Brazil in a clinic which regularly deals with suicidality. At this clinic, a strange Christmas tree was constructed by a team involved in stressful work at Christmas time. The Christmas tree was unusual in that it put on display a Santa Claus suiciding, which produced among participants and visitors a collective state of mind. This was where they felt mutually implicated but at the same time calmed, as a result of recognizing the presence of death at the time of Christmas celebration [9].

While it may not be uncontroversial philosophically to declare that a collectivity is “sick”, it can certainly be said that a collectivity is disordered, for example “having a nervous breakdown”, when its functioning is severely disrupted to the extent that it is outside the parameters of a normal range of behaviors. Specifically, when depression is overwhelmingly predominant, fear is so widespread that it is disabling, when rage leads to pro-active war, aggression to ethnic cleansing and genocide, and when suicide becomes widespread throughout the collectivity that the mental state can be considered disordered. There is also a positive side to collective mental state coming from the concept of “collective intelligence”, where the intelligence provided by a group is qualitatively superior to that of individuals [10].

Collective pathology presents a problem in that while individual pathology requires clinical evaluation, it can be questioned whether a group can ever be diagnosed collectively with an illness without making a value judgment [11]. At what stage can one call an evil act such as terrorism an act of psychiatric disorder? An answer to this problem is to consider an act which disrupts the normal functioning of a society as a disorder.

Some major types of disorder of the collective mental state could be identified as:

Collective depression

Endogenous conditions can be associated with the development of depression in individuals, and this can lead to a loss of belief including belief in a future [12]. Depression in individuals can lead to a sense of hopelessness which can become widespread so that one could refer to depression that is collective.

Depression can, in another view, be a result of a condition of learned helplessness, which can arise when undeserved punishment is inflicted on an individual, and this can be passed to others by contagion [13].

The psychological state of the Latin American world has been examined by the sociologist and philosopher Vigil who has diagnosed a state of collective depression, which he has found to be very similar as for depression in individuals: that is, a sense of disappointment, low self-esteem, guilt, amnesia and withdrawal [14]. Other collectivities may also be seen as ones in a similar condition of collective depression.

The burden of collective depression is by no means confined to the developing world. Many people, particularly young adults in affluent societies could be considered as showing symptoms of depression.

In the United States, The National Comorbidity Survey Replication study assessed DSM-IV major depressive disorder (MDD) and assessed work impairment with the WHO Health and Work Performance Questionnaire (HPQ). The prevalence rate for MDD was 6.4% in the previous 12 months additionally, annual human capital loss per ill worker was estimated at $4426 for the disorder. Annual projections to the US labor force were $36.6 billion for MDD [15].

The occurrence of collective depression created by regimes perceived as unfavourable or degrading creates instability because of the risk of entailing even worse regimes. Organization theory may make a contribution here as certain types of leadership can have "toxic effects" on organizational motivation [16].

Collective fear

Fear can be felt by a large number of people, particularly when it is communicated by contagion. A state of generalized anxiety can exist as a prelude to fear, and can be created by political leaders who are the intention to do so. Lake and Rothchild developed this observation:

“As groups begin to fear for their safety, dangerous and difficult-toresolve strategic dilemmas arise that contain within them the potential for tremendous violence...Ethnic activists and political entrepreneurs, operating within groups, build upon these fears of insecurity and polarise society” [17].

The insight here is that leadership that is so disposed can mobilize bystanders by mining their grievances, be they real or imaginary. Collective fear can find expression in acts of terrorism. As Orleans stated "This is the prime objective of terrorism: to alter the texture of daily lived reality by injecting a blend of apprehension, trepidation, despair and ruin" [18].

One example of this was when Hitler developed and exploited the well-founded mental state of fear among the German population of the advancing Soviet Red Army and prolonging World War 2. The transformation of individuals, families and communities from peaceful orientation into perpetrators of violence through the use of collective fear is a phenomenon that has been observed on many occasions by many writers as well as those mentioned above.

Collective aggression

The sources of aggression have long concerned psychologists, social scientists and philosophers. When it is collective, aggression can take the form of unprovoked war.

War can be open armed conflict between sovereign states or civil war with a state. Also within a state there can be a war of secession motivated by fear, or grievance over land, culture, language, religion or ideology. There can also be wars of independence between those seeking autonomy and an occupying state such as a colonizing power.

In civil war, such as the American Civil War (1861-1865), war was mechanized and the loss of life was very great, in fact higher than that of Americans in World War 2. In the Spanish Civil War (1936-1939) where the loss of life was also great, and even today, resentments are still felt by some descendants of participants. The American Civil War was about issues of race and central government, while the Spanish Civil War concerned issues of religion, land ownership and regional autonomy for Catalonia and the Basque Country, with some sympathy in Galicia. In the English Civil War (1642-1648), the issue was monarchy and change. Often the central issue in a civil war is identity, as expressed in difference of language and culture but whose expression is frustrated. The civil war in Sri Lanka (1983-2009) is an example of this [19]. All of the above mentioned civil wars could be described as reflecting a disordered collective mental state.

The motivation to aggression can include collective memories and interpretations of past events of a long time ago. In 1389 in the Battle of Kosovo, Islamic invaders took conquest of the Balkans, with the result that justifications for the conflict between Serbians and Kosovars, who are predominantly Islamic, in 1998.

In his analysis of the disintegration of the former Yugoslavia, the novelist Kis concluded that nationalism was the predominating causal factor. He diagnosed a state of collective and individual paranoia, describing collective paranoia as a combination of many individual paranoias, reaching a paroxysm in a group whose goal is resolve an issue of absolute importance, namely, the survival of the nation [20]. In this way, aggressive hyper-nationalism can be interpreted as a disordered collective mental state.

Collective aggression can also take the form of a desire for revenge affecting certain strata of society such as specific groups, communities, nations and even continents, such that the term collective vengeance can be used to describe the situation. A single event such as the assassination of a political leader can unleash a wave of collective violence leading ultimately to war or genocide. The shooting-down in 1994 by still-unknown persons of the aircraft carrying the President of Rwanda, Juvenal Habyarimana, was followed immediately by a genocidal attack on Tutsis by the majority Hutus, a clear example of collective aggression.

Collective desensitization

The philosopher Borkenau [21], in his study of collective violence, observed that severe changes to the social and political milieu can result in the acceptability of violence can become common, in other words a desensitization has occurred. As Borkenau expressed it:

“Once the carapace of custom is disrupted, the process acquires the characteristics of a chain reaction. Every rift opened by the devaluation of rules widens automatically and produces new rifts in other places....conduct becomes more and more irrational, the area of moral uncertainty is constantly widening, until the typical situation of the "dark ages," a situation of total insecurity and universal crime, is reached [21].

Killing can be interpreted as healing, as in suicide, and killing others can also be interpreted as therapeutic, healing, as in collective euthanasia. This is the case with wars of extermination, where whole categories of people are intended to disappear by genocide [22]. The war of extermination may be disguised as resettlement, as in the Black War in Tasmania or it may be large scale, as in the Third Reich where a number of categories of people were slated for disappearance [23] or Cambodia under the Pol Pot regime (1975-1979), which has been described as an autogenocide in that Cambodians themselves were the target group [24].

Thus, it can be hypothesized that a collective mental state can by contagion create aggression that can be allowed to develop through comprehensive collective desensitization. The implementation of policies leading to homicidal, genocidal and suicidal acts and other atrocities including mass rape and mass mutilation reveals that the common factor of a disordered collective mental state is present.

The existence of a collective mental state that may be disordered can have a causal role in the great questions of human society: wellbeing or depression, peace or war, accommodation or genocide, acceptance or discrimination.

Thus, the concept of the disordered collective mental state can provide a transdisciplinary vehicle for psychologists, psychiatrists, philosophers, historians, linguists and social scientists to work together on addressing the great issues facing humankind, of which the “collective nervous breakdown” is but one example.