The zapping racket of cicadas rising and falling, undulating in and out of sync wakes me up soon after sunrise. Although it’s not yet 7 a.m., the thick, steamy heat pours in through the open window in waves, and seems fused into one substance with the yazz and clatter of the insects.

Koichi Yamashita heads out into the rice fields in a verdant valley in Kochi Prefecture.

After gazing out the window at the shades of green in the valley and listening to the river far below chortling intermittently, I head down the steep staircase to join my hosts Koichi Yamashita and family for breakfast.

I am a guest at their small house at the end of a mountain road in remote southern Shikoku. Naturally, there is no air conditioner, and, as all our ancestors did for centuries, we adapt to the heat, and do not map out any particularly ambitious activities for the day. I am again reminded that environmentalism is often a matter of being at peace with not trying to accomplish too much.

After breakfast Yamashita takes me across the valley to the rice fields where he shows me how to use a hand-powered rice-cultivating machine, a device with a push-plowlike handle attached to two tiny metal boats, each of which has a rotating metal paddle in the middle. You push the boats through the muddy water, one boat on each side of the row of rice plants, and the paddles munch up any weeds that are growing in between.

While I bungle my way along trying not to run the paddles over the young rice plants, the sinewy Yamashita patrols the outskirts of the field, looking for holes in the bank left by moles, which can drain the whole paddy of water. Eleven-year-old Shanti, Yamashita’s second daughter, works alongside us in the hot sun pulling weeds. After a few hours, we head back to the house for lunch.

Rice farmer-philosopher Koichi Yamashita listens to his eldest daughter Himmalie, a fluent Bengali spleaker at age 15.

Before he was a rice farmer, Yamashita was a university professor in India with a Ph.D. in Hindu philosophy. Although he and his family have been living in this verdant valley for the past five years, before this they spent more than a decade living in India. There Yamashita taught Japanese language and literature at Shantiniketan University (founded by the renowned Indian poet and 1913 Nobel Prize winner Rabindranath Tagore) in the northeastern state of Bengal.

While teaching, Yamashita would commute between the rural campus of Shantiniketan and Calcutta University where he completed his Ph.D. His dissertation, based on Sanskrit documents from the 2nd through 4th centuries, was published under the title “Patanjala Yoga Philosophy with Reference to Buddhism.”

Yamashita also taught seminars on Meiji Era Japanese literature, lectured at international Buddhist scholarly conferences, published a book on Japanese grammar for Indian students and, with his partner Asha Amemiya, a walking guide for Japanese travelers to the holy places of Darjeeling.

But now, it seems, the philosopher finds most of his wisdom in the rice fields.

After lunch, we spend the hot afternoon sitting and talking in the deeply shaded house. The floorboards are stained a rich saddle brown and are shiny from years of people sitting and talking, living life on them. The afternoon light pours in from the open shoji doors and silhouettes the wafting, lazy smoke from the mosquito coil and Yamashita’s tiny conical bidi cigarettes.

He answers my questions in an easy and frank way, but seems mostly the type of person to listen and observe. His air is bemused. Around his head he wears a sweat-soaked strip of cotton cloth, his eyebrows arching over sad and contemplative eyes. His face is meditative and weathered, his voice is tenor and slightly raspy, and he laughs in a self-deprecating way. Overall his aspect suggests a life spent listening for the far-off sounds of vaguely sensed notions.

At about 2:30 p.m., when the heat is just reaching its peak, a large stinging fly zooms into the house. Several people in the room cringe instinctively, but in a hardly perceptible instant, Yamashita’s hand darts out, snags the madly careening bug, snaps it hard onto the wooden floor and then picks up and tosses the stunned insect out the open window. His face remains impassive.

Yamashita then explains to me that his book talks about some of the fundamental differences between Hindu and Buddhist ways of liberation — the former stressing the concept of atman, the true inner or transcendent self, which is thought to be identical with the all-pervading spirit of God, and the latter maintaining that such a “self” is not only false, but that thinking about this “self” is what gives birth to all suffering.

I ask him if he is still continuing his research, and by way of the answer, he just laughs.

“Naw! I just eventually couldn’t understand all that stuff. I threw up my hands. ‘I give up!’

“It’s all logical, of course, and I understand what those guys were saying, but as far as ‘satori’ and ’emancipation’ . . . yah!

“Yet when I’m by myself, out in the rice fields, working with the plants, I am simply glad. I understand that I myself am living, that I am in possession of a living spirit. In the field with the plants you just naturally develop a feeling of compassion, of love, of sympathy.”

According to Yamashita, the human body and the rice plant are not separate entities. “If you really make a thorough investigation of the question,” he says, “you will see that there is only one Life.

“Both rice plants and humans are made up the same substances: atoms and molecules. A rice plant is in possession of a life, just like a human. Humans aren’t ‘higher beings.’ That’s a mistake.”

Yamashita hands me a recent newspaper article he has written (in his mischievous tone) about natural farming in which he emphasizes the virtues of being lazy (“Don’t do unnecessary work”), stingy (“Don’t spend any money”) and not being greedy (“Don’t try to get more from the soil by using too much fertilizer.”)

Our discussion then wanders on to perhaps the most important luxury of living in the mountains: time. Although almost all the mountain people I’ve met grow and slowly prepare their own food — and that undoubtedly takes a lot of time — they seem to be suffused in timelessness, in an endless present.

“Think about eating a meal,” Yamashita says. “Nowadays, it’s possible to simply pop something in a microwave oven — ching! — it’s done, in one minute. But what about the hours you might have taken to grow the vegetables, harvest and cook them? That process is connected. You feel a sense of time. The process itself is life. Just popping something in the microwave — ching! — doesn’t give you sense of life.”

Then, bringing us finally back around to Hindu philosophy, especially the doctrine of ahimsa, or “non-harming,” Yamashita explains his thinking about the use of machines.

“I’m not ignorant of modern machines and tools, but I try to avoid doing things that cause harm — harm to other people, harm to other living things. A lot of machines, though, do cause harm — harm to people, harm to the Earth. It’s something to think about.”

Indeed it is.