Living with Gratitude for the Soil: Kukai's Teaching on Earth and Thankfulness

The Six Great Elements and the Meaning of Earth

Kukai's Six Great Elements philosophy teaches that everything in the universe is composed of six fundamental elements: earth, water, fire, wind, space, and consciousness. This framework, elaborated in his seminal works 'Sokushin Jobutsu Gi' (Attaining Buddhahood in This Very Body) and 'Himitsu Mandara Jujushinron' (The Ten Stages of Mind), forms the backbone of esoteric Buddhist cosmology. Among these six, the earth element symbolizes solidity, stability, and endurance — the very foundation of the material world.

The earth element encompasses far more than physical soil. Our skeletal structure, muscles, teeth, and nails — every solid component of the human body — are manifestations of the earth element. Kukai declared that 'the Six Great Elements are unobstructed and eternally in yoga,' meaning these elements interpenetrate one another and cannot be separated. Our bodies and the ground beneath us are made of the same fundamental substance. To touch the soil is to touch the earth element within ourselves.

It was no coincidence that Kukai established his monastic center on Mount Koya, at an elevation of roughly 800 meters deep in the Kii Mountains. He understood that practicing in an environment where one could directly feel the power of the earth was essential to spiritual development. Modern soil science has revealed that forest soil hosts thousands of microbial species in complex symbiotic relationships, but Kukai intuited 1,200 years ago that the earth is a living matrix nurturing countless forms of life.

Kukai and Gratitude for the Earth's Gifts

Kukai did not confine his reverence for the earth to abstract theology — he demonstrated it through action. The most celebrated example is his reconstruction of Manno Pond in Sanuki Province (present-day Kagawa Prefecture). This reservoir, one of the largest of its era, had repeatedly burst its banks, devastating local farmlands. Commissioned by the imperial court, Kukai is said to have completed this massive engineering project in roughly three months.

This was not mere civil engineering. For Kukai, it was an act of dana — selfless generosity — channeling the blessings of earth and water to enrich the lives of ordinary people. Harnessing the earth's power was, in his eyes, synonymous with embodying the Buddha's compassion. He also founded the Shugei Shuchiin, a school open to commoners regardless of social class, where agricultural knowledge was reportedly part of the curriculum.

On Mount Koya, monks have cultivated their own fields, gathered wild mountain vegetables, and sustained their community through the earth's generosity for over a millennium. Before meals, they recite the 'Gokan no Ge' (Five Contemplations), which includes reflecting on the immense labor and natural forces that produced each dish. In Kukai's time, practitioners would sit before a simple bowl of rice porridge and offer thanks to the soil that grew the grain, the rain that nourished it, the sun that warmed it, and the wind that carried its seeds.

Scientific Evidence for Our Connection to the Earth

Viewed through the lens of modern science, Kukai's teachings reveal a remarkable prescience. The practice known as 'earthing' or 'grounding' — walking barefoot on natural ground — has attracted growing research attention. Studies suggest that direct skin contact with the earth can reduce chronic inflammation, improve sleep quality, and normalize levels of cortisol, the primary stress hormone. A 2012 review published in the Journal of Environmental and Public Health concluded that electrical contact with the earth's surface may produce wide-ranging positive effects on human physiology.

Equally intriguing is research on Mycobacterium vaccae, a bacterium naturally present in soil. A 2007 study by researchers at the University of Bristol found that this microorganism activates serotonin-producing neurons in the brains of mice. In other words, the common experience of feeling uplifted after working in a garden has a measurable biological basis — soil bacteria can literally boost our mood.

Furthermore, the field of horticultural therapy has produced multiple clinical studies showing that touching soil and tending plants can alleviate symptoms of depression, lower blood pressure, and strengthen immune function. The sense of unity with the earth element that Kukai described 1,200 years ago is now being validated and enriched by contemporary science.

Practical Ways to Cultivate Soil Gratitude Today

Incorporating gratitude for the earth into daily life is more accessible than you might imagine. Here are five practices you can adopt gradually.

First, try barefoot walking. Spend just ten minutes a day walking on natural ground — a park lawn, a garden path, or a forest trail. As your soles register the warmth, coolness, softness, or firmness of the earth, your body absorbs knowledge that the intellect alone cannot grasp. The initial awkwardness fades quickly, replaced by a growing sensitivity and a tangible sense of connection.

Second, practice mealtime contemplation. Before eating, take a moment to visualize the land where your food was grown — the paddy mud that cradled rice grains, the dark loam that nourished vegetables. Silently offer thanks: 'I am grateful to the soil that raised this food.' This is a modern adaptation of the Five Contemplations recited by Mount Koya's monks for centuries.

Third, make soil contact a habit. Even a small balcony planter of herbs or cherry tomatoes counts. The full cycle — sowing seeds, watching sprouts emerge, watering, observing growth, and finally harvesting — is the most direct way to experience the earth's generosity. Beginners can start with resilient plants like basil, mint, or green onions.

Fourth, visit a Jizo statue. Jizo Bodhisattva is venerated as the being who draws infinite merit from the storehouse of the earth. Pausing at a neighborhood Jizo shrine to offer a prayer of gratitude for the ground beneath your feet is a beautiful fusion of Kukai's esoteric practice and Japanese folk devotion.

Fifth, observe seasonal soil. Notice how the same patch of ground changes through the year — soft and fragrant in spring, dry and cracked in summer, carpeted with decomposing leaves in autumn, frozen and silent in winter. Simply becoming aware of these transformations is itself a first step toward genuine gratitude.

Repaying the Earth and Our Environmental Responsibility

Kukai's earth-element philosophy carries urgent implications for today's environmental challenges. According to the Food and Agriculture Organization of the United Nations, the world loses approximately 24 billion tons of topsoil each year due to intensive farming and development. At current rates, some regions may exhaust their agriculturally viable topsoil within 60 years.

The concept of 'ho-on' — repaying a debt of gratitude — is central to Kukai's thought. To receive endlessly from the earth without giving back is to violate this principle. In practical terms, modern acts of earth-gratitude include composting kitchen scraps to return nutrients to the soil, supporting natural farming methods that avoid chemical fertilizers, and participating in local conservation efforts to protect woodlands and farmland.

In his 'Hizo Hoyaku' (Precious Key to the Secret Treasury), Kukai outlined ten stages of mental development. The lowest stage is dominated by animal instinct and raw desire. Treating the earth as nothing more than a resource to exploit corresponds precisely to this level. Recognizing our debt to the soil and accepting responsibility for passing its fertility on to future generations is, in Kukai's framework, an act of genuine spiritual growth.

Transformation Begins Beneath Your Feet

In Kukai's esoteric Buddhism, enlightenment is not a distant goal — it exists within this very body, in this very moment. In the same way, gratitude for the earth need not begin with grand environmental campaigns. It can start today, simply by looking down at the ground beneath your feet.

Tomorrow morning, as you step outside, notice the small blade of grass pushing through a crack in the pavement. That plant has driven its roots into a tiny pocket of soil and is living on the power of the earth. Simply noticing that tenacity softens something inside us.

In his 'Shoji Jisso Gi' (The Meaning of Sound, Word, and Reality), Kukai taught that everything in the universe is the Buddha's sermon. The cracks in dry earth, the scent of rain-soaked soil, the graceful furrows of a freshly plowed field — all are messages from the Buddha. Offering gratitude to the soil is nothing less than opening our ears to this cosmic teaching.

Set aside a few moments each day to direct your awareness to the ground. This is the simplest and most profound practice of gratitude that Kukai demonstrated 1,200 years ago. The transformation that begins beneath your feet holds the power, in time, to reshape the way you live.