In the 4th century BC, Aristotle admonished:

The man who is isolated, who is unable to share in the benefits of political association, or has no need to share because he is already self-sufficient, is no part of the polis, and must therefore be either a beast or a god.

Indeed, the ancient world held exile as the most formidable form of punishment, second only to execution, though in Greek tragedies it was often regarded as a fate worse than death. For more than two millennia, this fear and loathing of solitary life endured and permeated the fabric of society. In 1949, Yale anthropologist George Peter Murdock surveyed some 250 “representative cultures” across history and geography, and concluded:

The nuclear family is a universal human social grouping. Either as the sole prevailing form of the family or as the basic unit from which more complex familial forms are compounded, it exists as a distinct and strongly functional group in every known society. No exception, at least, has come to light.

Yet our relationship with solitary life has undergone a radical shift in the recent past. So argues NYU sociology, public policy, and media professor Eric Klinenberg in Going Solo: The Extraordinary Rise and Surprising Appeal of Living Alone (public library) — an ambitious exploration of what Klinenberg calls the “remarkable social experiment” that our species has embarked upon over the past half-century, juxtaposing the numbers with the enduring social stigma around singleness.

Until recently, most of us married young and parted only at death. If death came early, we remarried quickly; if late, we moved in with family, or they with us. Now we marry later. We divorce, and stay single for years or decades. We survive our spouses, and do whatever we can to avoid moving in with others — even, perhaps especially, our children. We cycle in and out of different living arrangements: alone, together, together alone […] [T]oday, for the first time in centuries, the majority of all American adults are single. The typical American will spend more of his or her adult life unmarried than married, and for much of this time he or she will live alone.

Klinenberg paints an even more vivid picture by the numbers:

In 1950, 22 percent of American adults were single. Four million lived alone, and they accounted for 9 percent of all households […] Today, more than 50 percent of American adults are single, and 31 million — roughly one out of every seven adults — live alone. […] People who live alone make up 28 percent of all U.S. households, which means that they are now tied with childless couples as the most prominent residential type — more common than the nuclear family, the multigenerational family, the roommate or group home.

To be sure, this trend is far from confined to the U.S. — the four countries with the highest rates of solo living are Sweden, Norway, Finland, and Denmark, where up to 45% of all households contain just one person. “By investing in each other’s social welfare and affirming their bonds of mutual support,” Klinenberg argues, “the Scandinavians have freed themselves to be on their own.”

Yet the sociocultural norms and dialogue around living solo haven’t caught up with these staggering statistics. As historian David Potter has famously noted:

In our literature, any story of the complete isolation, either physical or psychological, of a man from his fellowman, such as the story of Robinson Crusoe before he found a human footprint on the beach, is regarded as essentially a horror story.

Klinenberg puts it thusly:

Despite its prevalence, living alone is one of the least discussed and, consequently, most poorly understood issues of our time. […] Unfortunately, on those rare occasions when there is a public debate about the rise of living alone, commentators tend to present it as an unmitigated social problem, a sign of narcissism, fragmentation, and a diminished public life. Our morally charged conversations tend to frame the question of why so many people now live on their own around the false and misleading choice between the romanticized ideal of Father Knows Best and the glamorous enticements of Sex and the City. In fact…the reality of this great social experiment in living alone is far more interesting — and far less isolating — than these conversations would have us believe.

Klinenberg goes on to explore the forces and factors that have sparked the transformative social experience of living alone, which has in turn changed not only the way we understand ourselves and our most intimate relationships, but also the way we structure our cities and orchestrate our economies, demonstrating that solo living affects the lives of nearly everyone in the social ecosystem. He points to four key developments driving this cult of individualism, championed by Emerson and Thoreau: (1) The wealth generated by economic growth and the social security provided by the modern welfare state (“Put simply, one reason that more people live alone than ever before is that today more people can afford to do so.”); (2) the communications revolution (“For those who want to live alone, the Internet affords rich new ways to stay connected.”); (3) mass urbanization (“Subcultures thrive in cities, which tend to attract nonconformists who are able to find others like themselves in the dense variety of urban life.”); (4) increased longevity (“Because people are living longer than ever before — or, more specifically, because women often outlive their spouses by decades rather than years — aging alone has become an increasingly common experience.”).

Going Solo goes on to paint a richer portrait of this age of the singleton, covering a number of complementary forces — including, perhaps most interestingly, the rising status of women and their assertion of control over their own bodies (“[I]n 1950 there were more than two men for every woman on American college campuses, whereas today women make up the majority of undergraduate students as well as those who earn a bachelor’s degree.”). What emerges is a powerful set of questions about some of our most fundamental assumptions about what it means to be a part of society and, ultimately, what it means to be happy.