Understanding Loneliness: A Rough Theory

As a people, we are concerned—some might say obsessed—with the quality of our interpersonal relationships. . . . Loneliness is, so to speak, the opposite side of this coin.
Letitia Peplau & Daniel Perlman 

I have tried to put together a theory of loneliness. None of the concepts in the theory are my own. I hope merely to have made the relationships between these borrowed concepts clearer.

As even psychologists, who study loneliness professionally, are not yet ready with a definitive theory, what follows is but a rough one. 

What Is Loneliness? 

You are lonely if you experience negative emotions (or, negative affect) that are caused by deficient sociality. (This is a modification of the psychologist Jeffrey Young’s definition, presented in Loneliness, 1982.)[1]

The definition requires some clarifications. 

Deficient sociality is a subjective concept. Even if you had scrutinised a neighbour’s social life and found it wanting, you would still not know whether he was lonely. What matters is the neighbour’s opinion—Does he believe he has social deficits? 

Deficient sociality is of two types: insufficient sociality and poor sociality. 

Insufficient sociality is a problem of quantity.[2] It can be expressed in terms of how much time you spend in company—’Do you wish you met your friends more often?’—or the size of your social circle—’Do you wish you had more friends?’

Poor sociality, on the other hand, is a problem of quality—‘Do your relationships make you happy?’ 

The final clarification concerns the overlap between the concepts of solitude and loneliness. The two concepts are related, yet separate.

Solitude is the objective fact of being alone, and the people who lead solitary lives are called recluses. Voluntary recluses—e.g., hermits—are not lonely. The involuntary ones—e.g., prisoners in solitary confinement—are usually lonely, but even they may adapt to their reduced sociality, thus escaping loneliness. 

Loneliness, as already stated, involves subjectivity.[3] Hence, it is present among the ranks of the sociable as well. To paraphrase the title of a sociology book, you can be lonely in a crowd.

The definition of loneliness has some implications. 

The emotional flavour of loneliness depends on how you interpret deficient sociality. As there are several types of negative affect, the question is which one would define a particular instance of loneliness. Young writes, 

If they believe that they cannot function safely without the help of other people, they will experience anxiety. . . . If individuals blame others for their aloneness . . . they will feel angry or bitter. If they believe that they are responsible for not having close friendships . . . they will probably feel sad and may even become clinically depressed.

A related implication is that deficient sociality does not necessarily lead to loneliness. You may interpret deficient sociality in a way that does not lead to any negative affect at all. ‘If they view the problems as a challenge and believe they can readily close the gap by taking steps to develop closer relationships’, writes Young, ‘then they may not feel any negative emotion and therefore would not be labelled as lonely’.

Let us return to the example of the reclusive neighbour and suppose you had somehow managed to convince him of his social deficits. Before you could finally pin the label lonely on him, you would still need to know how he feels about it—Does his deficient sociality upset him? 

By combining the concepts described so far, the foundational concept of sociality itself can finally be defined and its relationship to loneliness made clearer.

Sociality is the measure, quantitative and qualitative, of your contact with society.

The quantity of social contact can be measured, both, objectively (by observers) and subjectively (by the individual). Although I can objectively count the hours my neighbour spends with his friends, only he can say whether those hours were sufficient.

The quality of social contact cannot be measured objectively; it can only be measured subjectively. Is my neighbour not the exclusive judge of how he feels about his relationships?

Writers frequently point out that loneliness is a word without an opposite. It remains unclear, however, what conclusion, if any, can be drawn from such a lack. (Apparently, several English words lack an opposite—Wikipedia gives the example of the word devout.)

But, what is loneliness? I mean what category of thing is it?

The answer is unclear. Academic papers variously refer to loneliness as an emotion, an experience, a feeling, a set of emotions, a situation, a state.

The social psychologist Daniel Perlman explained to me over email that there are those academics who implicitly view loneliness as an emotion and others who implicitly view emotions—at least, the negative ones—as being only a part of loneliness.[4]

Young—whose definition of loneliness I am relying on—evidently belongs to the latter camp.

What Are the Types of Loneliness?

The psychiatrist Aaron Beck, along with Young, has classified loneliness by duration: transient loneliness, situational loneliness, and chronic loneliness

Transient loneliness is a brief spell of loneliness, lasting at most for a few days. 

Situational loneliness is a sustained stretch of loneliness brought on by a major change in your sociality. With a duration sandwiched between those of transient loneliness and chronic loneliness, it would last longer than a few days, but be resolved sooner than two years.

The historian Fay Alberti calls major changes in sociality pinch-points: ‘adolescent love, the birth of a child, marriage, life-threatening illness or death, divorce, or any number of significant moments that can be experienced alongside others or alone’ (A Biography of Loneliness).

‘At each of these points,’ writes the historian David Vincent, ‘there is a prospect of periods of isolation as the individual maps out a new relationship landscape’ (A History of Solitude).

Chronic loneliness is a sustained stretch of loneliness that lasts for two years or more. 

What Causes Loneliness?

The sociologist Robert Weiss writes that there are two approaches to studying the cause of loneliness: ‘One considers situations in which loneliness is apt to occur . . . The other line of research considers personality characteristics . . .’ (Loneliness, 1982). 

In fact, the entire field of psychology is divided by the situation–person split. ‘Although these two camps have sometimes skirmished over the merits of focus­ing on situational versus dispositional variables’, write the psychologists Mark Leary and Rick Hoyle, ‘a full understanding of psycho­logical processes requires devoting attention to both’ (Handbook of Individual Differences in Social Behavior). 

A complete theory of loneliness, then, must bring together two categories of causes: situational and personal. Luckily for me, such a model already exists. It was created by Perlman and the social psychologist Letitia Peplau (Loneliness Research, 1984).[5]

In the Perlman-Peplau model, however, the distinction between situational and personal causes is not emphasised—something that I plan to do. Hence, the concepts from the original model will be shuffled, edited, sometimes deleted.

First, the situational causes.

Pinch-points may cause loneliness. Perlman and Peplau suggest that they are of three types: termination, physical separation, and status change. They write,

[F]or example, widowhood has been associated with loneliness by several researchers. . . . Such events as moving to a new community, going away from home to summer camp or to university, or spending extended periods in institutions such as hospitals or prisons all affect social relationships . . . [R]ole loss through retirement or unemployment typically disrupts social ties with former coworkers and so may precipitate loneliness. (Toward a Social Psychology of Loneliness)

Constraints on your lifestyle may also cause loneliness. Perlman and Peplau, once again, suggest that such constraints are of three types: time, distance, and money. They write, 

The student who carries a full course load and a heavy work schedule may have little time for sleep, let alone making friends. The firespotter who lives in a remote part of the forest has few opportunities to socialize. The single parent on a tight budget may not be able to afford the babysitter who would permit time for social activities.

(I think of a pinch-point as a sudden fall into loneliness and a lifestyle constraint as a gradual slide into it.)  

Anything that leads to poor relationships may cause loneliness. Here, Perlman and Peplau give the examples of competition, stress, and physical separation. They write,

Co-workers who are in direct competition for scarce resources may find it difficult to be supportive of each other. Families in situations of stress may find it hard to interact in positive, rewarding ways. Periods of separation make it difficult to maintain relationships that may once have been close and supportive.

Finally, dissimilarities may cause loneliness by making it difficult to initiate relationships. ‘People who are different from those around them’, write Perlman and Peplau, ‘—the one old person in the apartment building or the only Hispanic family on the block—may have fewer opportunities to start relationships’.

Now, a detour. We shift from the examination of discrete situations to that of whole cultures.

I suppose a society’s culture can be thought of as the fountainhead from which spring the situations—especially the common ones—that take place within the society.[6] You can further imagine some cultures leading to greater loneliness than others. The question, then, becomes ‘Which cultural values lead to an excess of the situational causes of loneliness?’

‘[S]ociologists have argued’, write Perlman and Peplau, ‘that secularization, mobility, and/or urbanization contribute to the high incidence of loneliness in American society’. They add, however, that these hypothesised causes ‘have not been subjected to empirical investigation’.

Those observations were made decades ago, in the 1980s. A more recent work is A Philosophy of Loneliness (2017), by the Norwegian philosopher Lars Svendsen. It includes a chapter called ‘Individualism and Loneliness’, which in turn includes sections on the rise of single-person households and the popularity of social media. Svendsen, however, argues against these hypothesised causes.

That individualism should lead to greater loneliness seems intuitive. ‘Loneliness was seen as a visible symptom’, writes Vincent, ‘of an increasingly unmanageable tension between the pursuit of material comfort and the conduct of stable and satisfying personal relations’. Research paints an altogether different picture: ‘The majority of the evidence tends to suggest lower levels of loneliness in individualistic compared to collectivist countries . . .’ (Loneliness Around the World).[7]

The rise in single-person households in a society inevitably alarms its social commentators. By contrast, Vincent and Svendsen have argued—independently of each other—against equating living alone and loneliness. Svendsen writes, ‘A person who chooses to live alone need not be more asocial than other people’. Vincent writes of ‘the critical distinction between time alone that is valued and embraced and the absence of intimate company that is a cause of negative emotions’.

The widespread use of the Internet—particularly, the popularity of social media—also has alarmed social commentators. The social psychologist Robert Kraut and his colleagues explain,

Many writers have worried that the ease of Internet communication might encourage people to spend more time alone, talking online with strangers or forming superficial ‘drive by’ relationships, at the expense of deeper discussion and companionship with friends and family. Further, even if people use the Internet to talk with close friends and family, these online discussions might displace higher quality face-to-face and telephone conversation. (Internet Paradox Revisited)

To see if the alarm is warranted, the loneliness researcher Sean Seepersad has reviewed the relevant academic literature in Addressing Loneliness. ‘[T]he Internet’, he writes, ‘is more of a tool and its effects on a person are dependent upon how it is used’. As for social media, he writes, ‘Research studies, looking at Facebook specifically, have not found that usage alone creates greater feelings of loneliness and social isolation’.

Cultural norms may also cause loneliness. Citing a study on students, Perlman and Peplau write,

If students were alone on weeknights, they reported only moderate feelings of loneliness, but students who were alone on Friday or Saturday nights reported intense feelings of loneliness. Here the expectation that weekends are for social activities appears to enhance students’ desired level of contact and thus to produce greater loneliness.

The discussion on loneliness sometimes devolves into what I call ‘the grand poetic vision of loneliness’. This lets loneliness be equated with any vague sense of dissatisfaction. Here is an example,

I wanted very much not to be where I was. In fact part of the trouble seemed to be that where I was wasn’t anywhere at all. My life felt empty and unreal and I was embarrassed about its thinness, the way one might be embarrassed about wearing a stained or threadbare piece of clothing. (The Lonely City)

Taken to its extreme, the grand poetic vision may blame loneliness for all of human suffering. Once again, an example,[8]

But one recurring topic was different. It wasn’t a frontline complaint. It wasn’t even identified directly as a health ailment. Loneliness ran like a dark thread through many of the more obvious issues that people brought to my attention, like addiction, violence, anxiety, and depression. . . .

It wasn’t always easy to tease out cause and effect, but clearly there was something about our disconnection from one another that was making people’s lives worse than they had to be. (Together)

Now, the personal causes. 

A lack of social skills may cause loneliness. ‘For example’, Perlman and Peplau write, ‘lonely students . . . report problems making friends, introducing themselves, participating in groups, enjoying parties, making phone calls to initiate social activities, and the like’.  

Certain personality traits may cause loneliness. Here, Perlman and Peplau mention low self-esteem, shyness, self-consciousness, introversion, lower affiliative tendencies, lack of assertiveness, and external locus of control. Instead of considering each of these traits individually, I will consider them together, creating a super-trait: the tendency to be lonely (or trait-loneliness).

Once again, a detour. Although trait-loneliness exists within the individual, a society’s average level of trait-loneliness can be calculated. The sociologist Pearl Dykstra calls such averages the society’s ‘population composition’ (Older Adult Loneliness: Myths and Realities).

Population composition is an explanation for differences in loneliness levels between societies. In other words, if a society is exceptionally lonely, perhaps it is because the trait-loneliness of its members is high.

We now know that loneliness in an individual may be caused by trait-loneliness, but what causes trait-loneliness itself?

The psychologists John Cacioppo and Louise Hawkley write that its heritability is around 48 per cent (Handbook of Individual Differences in Social Behavior).[9] Thus, almost half of the variation in trait-loneliness among individuals is because of differences in genes. The other half is because of the differences in the situations that the individuals have been through—in other words, because of the differences in their experiences. Childhood experiences are believed to be particularly influential.

Which genes cause trait-loneliness? The specific genes are yet unknown. The psychologist Luc Goossens and his colleagues suggest that the responsible genes would be among the ‘genes related to various neurotransmitters, signalling substances, and the immune system’ (The Genetics of Loneliness).

Which childhood experiences cause trait-loneliness? The question is largely unanswered. The psychologists Cindy Hazan and Phillip Shaver suggest that the quality of romantic relationships is affected by the quality of the relationships you had as a child with your parents. Hence, poor childhood relationships with parents may make you ‘especially vulnerable to loneliness’ as an adult (​​Romantic Love Conceptualized as an Attachment Process).[10]

We now know that trait-loneliness is caused by genes and experiences. A more fundamental question, however, remains unanswered. Why is such a trait a part of human psychology at all? To use biological terms—we have considered the proximate causes of loneliness, but now we will consider its ultimate cause. The cognitive psychologist Steven Pinker explains the difference,

To take a simple example, ultimately people crave sex in order to reproduce (because the ultimate cause of sex is reproduction), but proximately they may do everything they can not to reproduce (because the proximate cause of sex is pleasure). (The Blank Slate)

What, then, is the ultimate cause of loneliness, its evolutionary logic? Cacioppo and his colleagues provide the answer:

The early and extended dependence on caregivers and the limited physical endowments across the lifespan, together, place humans at risk when they are isolated. In this context, it may be adaptive to have evolved an aversive signal that draws attention to the prospect that our social connection to others is at risk . . . [J]ust as physical pain is an aversive signal that evolved to motivate one to take action that minimizes damage to one’s physical body, loneliness is an aversive state that motivates us to take action that minimizes damage to one’s social body. (​​Evolutionary Mechanisms for Loneliness).

The isolated individual would face risks not just from the natural environment, but from other humans too—such as ‘the severe competitive disadvantage of the lone individual confronting a group when both want the same resource’ (The Need to Belong).

Even once the individual has joined a group, he would still face risks if his relationships are of poor quality. Once again, Cacioppo and his colleagues explain:

Humans are capable of duplicity and changing alliances, so being with others is not sufficient to ensure one is embedded in a safe social surround, especially in vulnerable times such as when one is asleep. . . . [F]inding oneself uncertain that one can confide in, depend on, or trust others is not only an unhappy social environment, it can also be a profoundly unsafe social environment. Others with whom one once cooperated can no longer be counted on for cooperation, and strangers cannot be assumed to be friends rather than foes.

Loneliness, then, is a naturally-selected adaptation that protected our hunter-gatherer ancestors from the life-threatening risks of deficient sociality. That is its ultimate cause.

‘Working out how we came to have a capacity for loneliness may have no direct application’, writes Weiss, ‘but it may increase our acceptance of loneliness as a response as natural—and as valuable—as hunger.’ Accordingly, the types of loneliness can now be reconsidered.

Transient loneliness is perhaps essential to navigating a complex social environment. It motivates you to respond to minor changes in sociality, ‘on a minute-by-minute, hour-by-hour, and day-by-day basis in everyday life’ (Advances in Child Development and Behavior). Transient loneliness affects everyone without exception and requires no treatment.

Situational loneliness motivates you to respond to major changes in sociality.[11] To treat it, you would need to first identify the at-risk groups—individuals who have recently had a divorce, for example. Further, you may reduce its incidence through cultural reform—designing a culture that discourages divorce, again for example. On the other hand, you may view situational loneliness as a part of life, requiring neither treatment nor reduction in incidence.

Chronic loneliness remains a suffering without a purpose. It undoubtedly requires, both, a treatment and a reduction in incidence. ‘The condition we are studying is so disturbing’, writes Weiss, ‘that we surely have some responsibility to do what we can to be helpful to those who experience it’.

What causes, specifically, chronic loneliness?

A lack of social skills may cause chronic loneliness. As skills, by definition, can be learnt, treating this type of chronic loneliness should be simple.

A dysfunctional personality may cause chronic loneliness. Perhaps, benign situations make you lonely or you fail to make the necessary social course corrections, allowing transient and situational lonelinesses to become chronic. As personality, by definition, is enduring, treating this type of chronic loneliness (trait-loneliness) would be hard.

Unhelpful cognitive processes—described some paragraphs later—may cause chronic loneliness. This type of chronic loneliness can, self-evidently, be treated through cognitive behavioural therapy.

A society with a broken culture also may cause chronic loneliness. Perhaps, a culture has values leading to an excess of lonely situations or its norms set unrealistic standards for sociality. The incidence of this type of chronic loneliness can be reduced through cultural reform.

Can chronic loneliness be treated through antidepressants? To be sure, such medicines cannot fix deficient sociality, but they can indeed prevent negative affect. It follows that chronic loneliness can be treated in this way—although not cured.

The psychologist Stephanie Cacioppo and her colleagues have studied such treatments. They conclude that the usual treatments ‘may be more effective . . . if augmented initially by an appropriate pharmacologic treatment’ (Loneliness, 2015).[12]

As I have been repeating—loneliness is the combination of two phenomena, deficient sociality and the resultant negative affect. Therefore, the question of the cause of loneliness, in fact, comprises two sub-questions: ’What causes deficient sociality?’ and ‘How does deficient sociality lead to negative affect?’

Although the rest of the causes section tries to answer the first question, I try to briefly answer the second here.[13]

Perlman and Peplau suggest that deficient sociality leads to negative affect through cognitive processes. Such processes are of three types: attributions, social comparisons, and perceptions of personal control. In their words,

[W]hen people believe that their loneliness is due to factors that are both personal and unchangeable (e.g., their personality), depression and pessimism are more likely to accompany loneliness. . . .

Students who believe they have fewer friends than their age peers are apt to be lonely. . . .

Although both members of a couple typically reported loneliness and depression as a result of the breakup, partners who wanted the relationship to end and initiated the breakup were less distressed.

The cause of loneliness is a difficult question and, paradoxically, one with an abundance of answers. The many hypothesised causes are recapitulated in a diagram. 

In conclusion—if you are lonely, you can blame the species to which you belong, the culture of the society you live in, the situation you are currently in, or your own self.  

How Is Loneliness Measured?

As loneliness is a common experience, I assume that it can easily be identified and labelled within yourself. In other words, whenever you are lonely, you will know it. This section, however, concerns measuring loneliness in others. 

Being subjective, loneliness cannot be measured by observing social circumstances. I suppose, in the future, neuroscientists could directly examine the brain to check if you were lonely, but such technology does not exist today. Observing behaviour will also not work, as loneliness is not accompanied by any ‘consistent pattern of expressive behaviour or of action tendencies’ (Loneliness in Childhood and Adolescence).

Researchers seem to be left with only one way to measure loneliness: asking questions.

Loneliness is measured through questionnaires (or self-reports). These may be as direct and short as asking, ‘Are you lonely?’ They may even be indirect. ‘The primary difference’, write the psychologists Delroy Paulhus and Simine Vazire, ‘is that indirect self-reports usually obscure the construct being measured: Respondents may even be intentionally misled about the purpose of the test’ (Handbook of Research Methods in Personality Psychology). 

An indirect self-report, then, hides the fact that it is loneliness that is being measured. This is done by making sure its questions do not contain any form of the word ‘loneliness’. 

But why ask indirectly at all, when you can just as easily do so directly? Psychologists fear the effects of social desirability—’the tendency for peo­ple to present themselves in a generally fa­vourable fashion’ (Handbook of Individual Differences in Social Behavior). This takes the forms of self-deception and impression management.  

When measuring loneliness, social desirability becomes especially relevant. ‘Loneliness has generally been assumed by theorists and researchers to carry a negative social stigma’, write S. Lau and Gerald Gruen. ‘This assumption, however, has not been supported consistently by direct evidence’ (The Social Stigma of Loneliness).[14]

Accepting the assumption, the social psychologist Daniel Russell and his colleagues created the UCLA Loneliness Scale. It remains the most popular indirect self-report. Somewhat confusingly, its validation relies primarily on the results being correlated to those of direct self-reports.[15]

Given the definition of loneliness, you would expect an indirect self-report to look for signs of deficient sociality and negative affect. The UCLA Scale, however, focuses mainly on deficient sociality. I came across this observation in the work of the psychologists Molly Weeks and Steven Asher:

The most widely used assessment in the adult literature—the 20-item UCLA Loneliness Scale—contains very few items that could be viewed as asking directly about feelings of loneliness (i.e., ‘How often do you feel alone?’, ‘How often do you feel isolated from others?’), but instead focuses primarily on participants’ evaluations of different qualitative features of their social networks (e.g., ‘How often do you feel part of a group of friends?’, ‘How often do you feel that there are people who really understand you?’). (Advances in Child Development and Behavior)

Direct self-reports and the UCLA Scale, both, are currently being used by researchers. Being shorter, direct self-reports are convenient for large-scale studies.

The two measures sometimes disagree. The popular science book Loneliness (2008) describes such a disagreement, in the curious case of a Mr Diamantides:

When you ask how he is, his response is an emphatic ‘I’m wonderful’. . . . ‘I connect well with people’, he says. . . . When he talks about social connection, he peppers his description of his life with phrases like ‘I’m just lucky’; ‘I’m blessed’ . . .

The same Diamantides, however, received a high score on the UCLA Scale. This contradiction could have been resolved by administering a third test—one measuring social desirability.

The authors, having absolute confidence in the UCLA Scale, chose another solution. Like detectives, they combed through Diamantides’s direct self-report looking for inconsistencies. Concluding that his statements were indeed tainted by social desirability, they wrote,

The point is that people can misuse their powers of cognition in their attempts to self-regulate the pain of feeling like an outsider. They can create a false persona—a practice commonly known as self-deception—that frames their life the way they want it to appear.

How Common Is Loneliness?

I am not addressing the effect of the COVID-19 lockdowns, so I suppose the question should properly be, ‘How common was loneliness before the COVID-19 pandemic?’

Loneliness is measured by assuming that it has degrees. (You and I may both be lonely, but perhaps one of us is lonelier than the other.) Thus, loneliness would exist on a continuum: At one extreme, you would not be lonely at all; at the other, you would be as lonely as possible. 

Svendsen has noted that direct measures find your place on the continuum by asking either how often you are lonely (never, rarely, sometimes, often, always) or how much loneliness bothers you (not at all, a little, a lot).

We know that the UCLA Scale asks about loneliness indirectly. Based on the answers, it calculates a score, determining where on the continuum you lie. ‘High loneliness is defined as scoring 44 or higher’, write Cacioppo and William Patrick. ‘Low loneliness is defined as scoring less than 28. A score of 33 to 39 represents the middle of the spectrum’ (Loneliness, 2008). Presumably, getting the minimum score of 20 would mean you are not lonely at all.  

Such approaches make it meaningless to then ask, ‘How many people are lonely?’ Except for the ones who chose never or not at all in a direct measure or scored a perfect 20 on the UCLA Scale—everyone would get counted among the lonely. ‘That is like lumping together a group of people with chronic migraines and a group who get a small headache every now and then’, writes Svendsen, ‘as if they were identical’.  

The design of loneliness research prevents us from knowing how many are lonely. It does allow us, however, to know how many are severely lonely. 

In England, Vincent believes that the proportion who are lonely often or always is around five per cent. For Norway, Svendsen has tabulated the government’s statistics. The lastest entries show that the proportion of men who are very bothered or extremely bothered is around four per cent. For women, it is around seven per cent.

Which are the loneliest countries? This question cannot be answered as we do not have the data for all countries.

In Europe—where most cross-national research takes place—the southern countries are lonelier than the northern ones. The post-Soviet states, too, are very lonely. (​​Cross-National Differences in Older Adult Loneliness)

Is loneliness increasing? Dykstra has reviewed the research from European countries. ‘[A] consistent pattern emerges with regard to the proportion of people who often (or persistently) feel lonely’, she writes. ‘Contrary to popular belief, this proportion has not increased over time. Studies show either a decrease or no change over time.’

What is the ‘popular belief’ that Dykstra has referred to? ‘The media seems to have agreed that rich countries are experiencing a loneliness epidemic’, writes the economist Esteban Ortiz-Ospina. ‘There are literally thousands of newspaper articles that use this exact expression.’ (Is There a Loneliness Epidemic?)

How is this myth propagated? Vincent charges the media with ‘the constant tendency to fly to extremes of negative estimation’ and ‘a growing propensity to appropriate anxieties about well-established public health threats such as cigarettes, obesity, substance abuse, and dementia’. Svendsen worries that even though the studies that find a big rise in loneliness remain the exceptions, they ‘receive the greatest media attention’.


Although there is much that we do not know about loneliness, the accumulated research is still a vast space. Within this known universe of loneliness, the constellations that a psychologist will see depends on which dots he chooses to connect.

This article was simply a collection of the patterns that I have chosen to see.

Here are two additional articles of mine that cover topics related to loneliness: ‘What Is Solitude?’ and ‘Why Are Some People Introverts?


The featured image for this article—visible when shared on social media—is a photograph of Edward Hopper’s Nighthawks. The photograph was downloaded from Wikimedia Commons and, then, cropped.

1. Here is Young’s original definition: ‘I define loneliness as the absence or perceived absence of satisfying social relationships, accompanied by symptoms of psychological distress that are related to the actual or perceived absence.’

My reading of the definition is that it encompasses three separate questions: Is there an objective social deficit, is there a subjective realisation of a social deficit, and is there any resultant negative affect?

The implications of these questions are shown in the following diagram.

Young’s original definition differs significantly from my modified version, which is wholly unconcerned with objective social deficits.​​^

2. An excess of sociality, the opposite of insufficient sociality, is also a problem. It is a problem of quantity—’Do you wish you could spend more time by yourself?’ Excessive sociality cannot cause loneliness, however.​​^

3. Psychologists call an objective lack of sociality social isolation.​​^

4. The psychologists who study emotions would object to me using the words emotion and affect as synonyms!​​^

5. Whenever I cite Perlman and Peplau in this article, I am referring to their paper ‘Loneliness Research’ (1984), unless I explicitly mention a different one.​​^

6. The sociologist Pearl Dykstra notes that countries differ because of their ‘cultural systems, economic organisation, policy arrangements’ (Older Adult Loneliness: Myths and Realities).

I am using the word culture in a broad sense to include all such differences.^

7. The original analysis presented in the paper did in fact find individualism to be a cause of loneliness.​​^

8. Although my examples are new, the grand poetic vision itself is decades old. ‘In post-war social studies’, writes Svendsen, ‘loneliness essentially comprises the “standard diagnosis” of modern life . . .’​​^

9. If you are wondering how heritability is calculated, it is through twin studies.​​^

10. Hazan and Shaver have based their work on John Bowlby’s Attachment Theory—a theory I find unconvincing.​​^

11. The possible responses, to major changes in sociality, are of two types: decreasing desired sociality and increasing achieved sociality.

To decrease desired sociality, Perlman and Peplau suggest adaptation (i.e., accepting your current level of sociality), task choice (i.e., cultivating solitary hobbies), and changed standards (i.e., reducing ‘standards for who is acceptable as a friend’).

To increase achieved sociality, Perlman and Peplau suggest ‘making oneself more physically attractive, joining clubs, initiating conversations with other people, deepening existing relationships’.

(Toward a Social Psychology of Loneliness)​​^

12. Relying on the definition of loneliness, the diagram below shows that treatment may target any one of four points.

Moving from left to right—reducing desired sociality is the first point of treatment. Increasing achieved sociality is the second. Breaking the connection between deficient sociality and negative affect is the third. Stopping negative affect is the fourth.

Perlman and Peplau had identified the first three treatment points, to which I have now added a fourth (Toward a Social Psychology of Loneliness).​​^

13. Young’s views on how cognitive processes translate deficient sociality into negative affect have already been presented in the ‘What Is Loneliness?’ section.​​^

14. The original analysis presented in the paper did in fact find loneliness to be stigmatised.^

15. We know that the UCLA Scale does indeed measure loneliness because of the several tests that it has been put through.

The primary proof—already mentioned—is that the UCLA Scale is correlated to direct self-reports. Additionally, it had provided high scores to the patients of a loneliness clinic.

The UCLA Scale is correlated to negative affect—such as depression—which accompanies loneliness, yet is not a measure of negative affect in general (discriminant validity).

The scale is correlated to causes of loneliness—such as being single. It is negatively correlated to phenomena theoretically incompatible with loneliness—such as social support. It is uncorrelated to phenomena unrelated to loneliness—such as being hard-working.

Finally, the UCLA Scale is unaffected by social desirability.

(Developing a Measure of Loneliness; The Revised UCLA Loneliness Scale; UCLA Loneliness Scale Version 3)​​^