Exercise your brain and body, keep engaged with work and friends

When David H. Murdock declared, “Exercise your brain and body, keep engaged with work and friends, and feed your brain with a healthy, plant-based diet — as well as knowledge,” he was not simply offering a rule for longevity — he was revealing a philosophy of harmony. His words flow like an ancient teaching, joining together the three great pillars of a full life: motion, connection, and nourishment. To truly live, he reminds us, is to move, to think, to love, and to learn — for when any of these falter, the human flame begins to dim.

At its heart, this quote speaks of balance between the physical and the spiritual, between what feeds the body and what feeds the mind. Murdock, a man who has dedicated much of his life to the study of health and nutrition, saw that one cannot thrive through food alone, nor through intellect alone. The body must move as the mind must grow, and the heart must remain open to companionship. Like the ancient philosophers who spoke of the unity between nature and man, he saw that life itself is a garden — one that withers when neglected and blossoms when tended with mindful care.

The origin of this wisdom lies in a principle as old as civilization: that health is not the absence of illness, but the presence of purpose. In Greece, Hippocrates — the father of medicine — taught that “walking is man’s best medicine” and that food should be our first form of healing. But even he warned that the mind must not be starved, for ignorance is a deeper sickness than any ailment of the flesh. In Murdock’s modern echo of this ancient truth, the plant-based diet symbolizes not just clean eating, but purity — a return to what is natural, untainted, and life-giving. It is the diet of the earth, the way our ancestors lived in rhythm with creation.

But Murdock’s command to exercise your brain carries a second, deeper light. It calls us to resist stagnation — to stretch not only our limbs, but our thoughts. In the same way that the body weakens without movement, so too does the mind decay when left unchallenged. Consider the story of Leonardo da Vinci, whose insatiable curiosity kept him youthful until his final days. He was a painter, inventor, scientist, philosopher — his brain forever at play. He showed the world that the mind grows sharper not through routine, but through wonder. This is the exercise of thought: not repetition, but discovery.

And then, there is his call to keep engaged with work and friends. Here lies a truth that transcends all ages — that human connection is medicine. The elders of every tribe, the monks of every monastery, the sages of every temple have all spoken of this: isolation is slow death, while community renews the spirit. To share labor, laughter, and conversation is to remain part of life’s grand pulse. Just as blood must flow through the veins, so must friendship flow through the heart. A person who keeps company with joy will rarely grow old in spirit.

This harmony between action, nourishment, and connection is what the ancients called eudaimonia — the flourishing of the soul. Murdock’s advice may sound simple, yet it contains the architecture of a full human existence. For what good is a strong body without thought? What worth has intelligence without compassion? And what value has a long life, if it is lived alone or without purpose? The wisdom of his words is that all these things — food, learning, labor, and friendship — are not separate paths, but one road leading to vitality and peace.

So, my listener, remember this teaching: move your body daily, for motion is life’s language. Feed your mind not only with food from the soil, but with the fruits of wisdom, curiosity, and conversation. Cherish your friends, for they keep your soul bright and your heart awake. The ancients believed that to live well was to be in harmony with the rhythm of the universe — neither clinging to youth nor fearing age. Follow Murdock’s wisdom, and you too shall live as they did: not merely long, but deeply, consciously, and joyfully — a whole being in balance with body, mind, and earth.