When the novelist Chiyo Uno died in 1996 at age 98, she was as extravagantly eulogized for her love life as for her literary work. Four marriages, four divorces, several high-profile love affairs, one attempted love suicide — now that was living! Society disapproved? That should have been her biggest worry. Life in all its forms was there for the seizing, and she would seize it come hell or high water.

In her erotic heyday — the 1920s and ’30s — she must have struck those squirming in the straitjacket of a straight-laced society as being far ahead of her time: a model to be imitated if only they had the courage; a living symbol of a liberated future.

But by the sad mid-’90s, the shower of tributes notwithstanding, she already seemed a little passe, and in the first years of the new century, her kind seems almost extinct, not only because society is long past caring how its individual members live their private lives (elected officials and sports celebrities perhaps excepted), but because of the dull, gray solitude that seems to have descended upon the Japanese people.

An NHK TV special in January gave it a name that stuck: muen shakai — a “no-relationship society.” The weekly Shukan Diamond made it the subject of a cover story in April. The starkest statistic among many is the number of people dying alone at home — some 32,000 a year. Sometimes weeks go by before anyone notices.

Isolation has been deepening over the years. A survey conducted by the Organisation for Economic Co-operation and Development (OECD) titled “Society at a Glance 2006,” cited by Shukan Diamond, includes a comparison among 20 nations of the percentage of people claiming to have no or almost no interaction with family, friends, colleagues or social groups.

In no other country are people as unconnected as the Japanese, 15.27 percent of whom say they have almost no social relations. The nearest runnerup is Mexico with 14.05 percent. The OECD average is 6.7 percent. The gregarious Americans (3.11 percent) come across as among the least lonely, though the Irish (2.93 percent) and the Dutch (2.01 percent) have them beat. A contributing factor is the declining allure of marriage. In 1920, Shukan Diamond’s research shows, lifetime singles, male and female, accounted for about 2 percent of Japan’s population, a ratio that held steady for the next 40 years. The ’60s and ’70s saw a gradual rise in the number of unmarried women; and in the ’90s, a surge in unmarried men that continues to this day. By 2005, 16 percent of men and 7 percent of women were single and intending to stay that way.

A pinched economy pinches ideals. The weekly Spa! last month profiled several unmarried men in their mid-30s. Some were single by choice, others by force of circumstance. Surveys show an overwhelming majority of singles — 78.3 percent in Spa! study — saying they want to marry eventually; but the data suggest the desire is strongest in those who, whether due to extreme shyness or the sheer financial impossibility of the undertaking, have the least hope of proceeding. Typical of those happy enough to stay single is a 35-year-old cell-phone marketer who confides to Spa! his inward response to his girlfriend’s recurring suggestion that they marry before her biological clock runs out: “Thoughts of having a child make me shudder.”

As with love, so with friendship, as Spa! claimed to discover back in March. Polling 300 men in their 30s, it found 35.4 percent of them do not have a single close friend. Cybernetworks have woven us into a web that seems to starve the more traditional forms of togetherness.

Most extreme among all the various degrees of isolation is the state known as hikikomori, total social withdrawal. The phenomenon arose in the intensely competitive ’80s and proliferated in the depressed ’90s, affecting an estimated 1 million people. Typically beginning with an inability to face school, it develops into an inability to face anything beyond the walls of one’s bedroom.

In last week’s Shukan Asahi, a doctor who runs a hikikomori outpatient clinic in Niigata Prefecture describes a man who has suffered from hikikomori for 23 years: “His teeth are falling out, his body is shrinking, his muscles have atrophied. Chronologically he’s 40, mentally he’s 17, physically he’s an old man.”

“Love is the answer,” it used to be said. Chiyo Uno certainly thought so. Maybe it’s still true in a way. Last month, Shukan Post surveyed 100 middle-aged wives who expressed various degrees of sexual discontent — but when asked if they loved their husbands, 71 percent of respondents said they did. That’s hopeful, if only ambiguously so.