The Geometry of Obon

What a Japanese festival for the dead can teach us about aging, community and mathematics?

I think about lines and circles alot!

My earliest memory is in primary school.

I cannot remember his name, the classroom, or even exactly how old I was, but I remember one lesson clearly. The teacher drew a line across the blackboard and asked us what it was. A line, obviously. He explained that what he had drawn wasn’t really the line at all. It was only the tiny bit of the line we could see. Mathematically, it carried on beyond the chalkboard, through the classroom wall, past the school, across whatever lay beyond it and, theoretically, forever.

I remember almost looking up from the blackboard and trying to follow it.

Wow.

Geometry was suddenly elevated in my mind and soul from just being a class at school to something much bigger. A few inches of chalk had lifted my eyes beyond the room and into infinity. I didn’t have the language for it then, but that idea lodged somewhere deep and never left.

Years later, while writing Boys Becoming Men, my book about rites of passage, I found myself thinking about lines again, although this time not as a mathematical curiosity. but how linear thinking shapes the way we organize life. We have timelines and deadlines, pipelines and bottom lines. We talk about career progression, moving forward, getting ahead, and eventually reaching the end of the line. Top Line, bottom line. The list goes on. None of this is wrong. Lines are extraordinarily useful. They give us direction, enable progress, and help us get things done. The problem begins when we assume that life itself should work the same way.

And living in Japan at the time ( still do), I became aware that another geometry was operating alongside the line: the circle. I saw it in seasons and festivals, in agriculture and community rituals, in the continuing presence of ancestors, and eventually in my research into aging and longevity.

This week that circle is particularly visible because Japan is in the middle of Obon.

This week families are welcoming their ancestors home. Graves are cleaned, lanterns are lit, and people return to their hometowns. At Bon Odori gatherings, generations dance together around a central yagura. The choreography varies, but the image remains literal: people move in a circle.

I find that fascinating because Obon does something our modern linear imagination finds difficult. It allows past, present, and future to occupy the same space. The ancestors have not disappeared off the end of a timeline. They remain part of the family story and, for these few days, are symbolically welcomed back into it.

I have been circling a related thought for years now, which I address more directly in my work on longevity: I have misgivings about the modern nuclear family as the default unit around which we organize society.

I am not against families, of course. Nor am I arguing for a return to some idealized Japanese past. I am talking about the nuclear family as a relatively recent social ideal: parents and children functioning as a largely self-contained unit, with each generation eventually leaving to create another unit of its own and the older generation fading into irrelevance. It fits the linear worldview beautifully. We are born, raised, launched, become independent, create another household, and always keep looking forward.

There is some value in that. It helps enable mobility, independence, personal freedom, and reinvention. But it comes at a cost, particularly as we grow old. If every generation moves forward and away, older people can eventually find themselves standing behind the active family unit rather than remaining within it.

The circle works differently. Its underlying question is not only, “Where am I going?” but “What am I still part of?”

This week. I was being consulted by a business analyst who is developing strategic thinking around aging in Japan. As we talked, I described some of what I have observed about the circular and cyclical nature of Japanese society and how different that can be from the linear assumptions built into much Western business thinking. She latched onto that, the physical manifestation of a light going in the head; Eyes widened, and jaw dropped. Later in the conversation, she returned to that moment and said it helped her see things differently. It offered another lens through which to view aging, not merely as a demographic trajectory to be managed but as a question of where people remain situated within society as they grow older.

The conversation reminded me why I keep returning to this subject. Lines and circles are not just metaphors. They influence the questions we ask.

If aging is primarily understood as a line, our attention naturally turns toward extending it. How many years can we add? How long can somebody remain productive? How do we delay decline? These are important questions, and medicine has made extraordinary progress answering them.

But the circle prompts another set of questions. Where does an older person belong? Who still expects them to turn up? What do they contribute? Who notices when they don’t appear? What happens to their role as their physical capacities change?

Those questions lie close to the heart of what I call the Art of Community.

During my research across Japan, I have repeatedly encountered older people whose lives remain woven into something larger than themselves. Sometimes that is family, but often it isn’t. It might be neighbors, a festival committee, Radio Taiso, a gardening group, karaoke, volunteering, or simply the web of relationships accumulated over decades of living in one place. What interests me is not whether these people are constantly being “cared for.” Often they are not. What matters is that they are still visible, still participating, and still expected somewhere. And undergirding all that, they remain within the circle that is moving, dynamic, and multigenerational.

I should add an important qualification because I have no interest in looking at Japan through rose-tinted glasses. Japan has loneliness. It has ageism. It has people dying alone. Traditional community can become oppressive, and the same circle that provides belonging can also demand conformity and obligation. Many feel and complain that the old Japanese family system placed burdens on people, often women in particular. Nor do I think “Japan does it better” is a useful conclusion.

What I do believe, after almost three decades here and several years spent concentrating particularly on aging, is that there are still visible pieces of social architecture in Japan worth examining before it becomes the lost art of community.

Now, back to the annual Obon season and how it relates.

Obon reminds us that a community can extend backward as well as forward. The people who came before us remain part of who we are, while those who grow old do not automatically cease to belong because their economically productive years are behind them.

And yet there is a growing tension inside that beautiful image.

Japan’s families are becoming smaller. Rural communities are shrinking. More older people are living alone. The traditional household structures that once kept generations within the same social orbit are weakening, and some of the people reaching their eighties and nineties today may belong to the last cohort who inherited those structures almost unconsciously.

That does not mean Japan should turn back the clock. I think it means something more interesting. The circle has to become larger than the family.

If the old biological circle is weakening, the answer is not to force children back into obligations they have rejected. It is to understand what that circle once accomplished and find new ways of doing it through neighborhoods, friendships, associations, workplaces and chosen communities.

That is what Obon has me thinking about this year.

My mathematics teacher taught me to look beyond the piece of line I could see and imagine how far it might travel.

Japan has spent the past thirty years teaching me something about the strength of the circle. And I have increasingly begun to see that circle as a wheel: turning and moving, yet keeping its parts connected.

Going Deeper

In the Full Edition on Substack, Defying the Red Zone, I take that image further and explore what happens when we think of the circle as a wheel, particularly where older people sit within it and why remaining connected can also mean remaining visible. I look at where our linear assumptions about family and aging came from, how the traditional Japanese ie created a very different form of continuity, and why neither model should be romanticized.

I also examine the rapid growth of older people living alone in Japan, isolated deaths, and changing relationships with ancestral graves, asking what might be preserved from the old circular architecture without recreating its restrictions. Finally, I take those observations into practice and consider what a more circular approach to aging could mean for families, communities, business, health, and public policy. Here is a link if you are interested: https://japansolo.substack.com/p/the-geometry-of-obon?r=29en6p&utm_campaign=post&utm_medium=web&showWelcomeOnShare=true