Keep well; that is the half of wisdom and of happiness.

The French novelist and thinker Émile Zola, whose pen carved truth into the conscience of his time, once said: “Keep well; that is the half of wisdom and of happiness.” Simple though it sounds, these words carry the weight of centuries of forgotten understanding. In them lies the eternal law that the ancients knew well: that the body is the servant of the soul, and that to neglect one is to wound the other. Zola, who lived in an age of industrial smoke and spiritual struggle, understood that wisdom and happiness cannot live in the heart of one who is unwell—physically, mentally, or morally. For health is not merely the absence of sickness; it is the harmony of life within us, the silent accord between mind, body, and spirit.

To keep well is not a selfish act, but a sacred duty. It is the foundation upon which all greatness rests. The farmer cannot till the soil if his hands tremble with fever; the scholar cannot write if his body collapses under strain; the lover cannot give warmth if their own flame is dying. Thus, Zola’s words remind us that health is the vessel through which wisdom and joy are carried. Without it, even the most brilliant mind will wither, and even the richest heart will ache. The ancients called this harmony sophrosyne—the discipline of moderation, where one lives in balance with the rhythms of nature and the limits of one’s own being.

In Zola’s world, this teaching was not abstract. He lived in an era of exhaustion—men working in factories until their lungs turned black, women breaking under the weight of labor and poverty, thinkers burning their strength in restless pursuit of ideals. He saw that humanity, in its hunger for progress, was sacrificing its very health—the essence of its happiness. And so, his counsel was not merely about the care of the body, but about the wisdom of self-preservation, of understanding that true progress, true happiness, must never come at the expense of one’s vitality. To “keep well” is, in truth, an act of rebellion against self-destruction.

The history of the world itself bears witness to this truth. Consider the life of Leonardo da Vinci, that divine artist of Florence, who lived in harmony with his body and his spirit. He rose with the sun, ate in moderation, walked among nature, and treated his health as a discipline of the mind. Through this balance, his genius endured for decades, flowering into works that still breathe with life. Now contrast him with Franz Kafka, whose frail health tormented his days and cut short his gift. Though his mind soared with insight, his body could not sustain the burden. Here we see what Zola meant: that wellness is not a luxury—it is half of wisdom and half of happiness, for without it, the highest dreams fall silent before their time.

To keep well, one must also guard the soul. The mind, poisoned by bitterness or fear, can sicken the body as surely as hunger or disease. The one who fills their thoughts with anger may find their heart heavy and their body weak; the one who cultivates peace and gratitude will find their strength renewed. The wise of old knew this truth. In the temples of Greece, medicine and philosophy were sisters; healing was not of the flesh alone, but of the spirit. So must it be for us. Health is not merely physical—it is moral, emotional, spiritual. To be well is to live truthfully, to think purely, and to love deeply.

Zola’s message, therefore, is both gentle and commanding: care for yourself as you would care for a beloved friend. Let the mind rest as the body labors, and let the body rest as the mind dreams. Rise with the dawn, breathe the clean air, eat not for indulgence but for strength, walk where the earth still remembers the sky. Above all, do not drive yourself into ruin for ambition, for work, or for worry. For no wisdom endures in a broken vessel, and no happiness blooms in an exhausted soul. To “keep well” is to prepare the ground upon which all virtue and joy may grow.

So, my children of this age, guard your wellness as your first treasure. Seek balance, not excess. Honor sleep, simplicity, and peace. Feed your body with care and your mind with beauty. Remember that happiness is not born in pleasure but in wholeness, and that wisdom cannot thrive in one who is unwell. Zola, with the insight of a man who saw both glory and decay, gave us a truth worth carrying through the ages: to live well, you must keep well. For health is not merely half of wisdom and happiness—it is the bridge that joins them into one radiant, enduring whole.