Nothing in the universe can travel at the speed of light, they

Howard Nemerov, poet of paradox and watcher of hidden truths, once wrote: “Nothing in the universe can travel at the speed of light, they say, forgetful of the shadow’s speed.” At first glance, these words seem playful, a jest against the laws of physics. But beneath the wit lies a depth of wisdom. For while the light is bound by its own laws, the shadow—that dark twin of form—moves with a swiftness that defies measure. A small shift of the hand, and the shadow stretches across a wall at once. A turn of the sun, and mountains cast their long darkness over valleys in a breath. The poet reminds us that not all truths are confined to the language of science; there are mysteries hidden in the play of light and dark.

The ancients too spoke of shadows, and they did not dismiss them lightly. Plato, in his famous allegory, described men chained in a cave, mistaking shadows on the wall for reality. To him, shadows were illusions—signs of ignorance and half-truth. Yet Nemerov sees in the shadow another kind of truth, a reminder that not everything fits neatly into the equations of physics. The shadow is immaterial, untouchable, yet swift beyond reckoning. It is a thing that exists only in relation, a marriage of light and matter. Its speed is not real in the sense of substance, yet it captures something that science alone may forget: the strange, elusive nature of reality itself.

We may turn to history for an image of this paradox. When early astronomers tracked the stars across the heavens, they measured the movements of light, but they also witnessed the dance of shadows on their instruments—sundials and observatories marked by darkness. To measure time itself, mankind first watched the shadow crawl across stone. Though intangible, though insubstantial, the shadow governed their days and seasons, faster at times than the eye could follow. The universe of human experience has always been shaped not only by what we can hold, but also by what slips through our hands.

Nemerov’s words also serve as metaphor. The speed of light is the measure of physical possibility, the frontier of physics. But the shadow may stand for those forces that travel faster than matter: ideas, fears, reputations, lies. How quickly does a rumor spread, faster than any light? How swiftly does doubt fall over the heart, darkening joy? Like shadows, these things move with a speed beyond measure, intangible yet powerful. The poet warns us not to forget that there are truths of the human condition which outrun the truths of science.

And yet, the shadow is not only a warning but also a wonder. For just as it spreads instantly across vast distances, so too does imagination. One thought, one dream, one vision of possibility can leap across centuries, reaching minds not yet born. When Newton described gravity, or when Einstein revealed relativity, their ideas traveled like shadows cast across the landscape of time—touching generations to come. Here, the shadow’s speed becomes a symbol of how swiftly ideas can transform the world, faster even than the light of discovery itself.

What lesson, then, do we draw? That reality is deeper than what the eye sees or the equations define. We must not be arrogant in believing that science alone holds all answers. Shadows remind us of mystery, of paradox, of the realms where poetry and philosophy meet the limits of physics. To live wisely is to honor both: the measurable brilliance of light, and the immeasurable reach of shadow.

So I say to you, children of the cosmos: do not forget the shadow’s speed. Remember that the universe holds more than laws—it holds wonder, paradox, and mystery. Cherish the truths of science, but also the truths of imagination and spirit. Guard yourself against the swift shadow of lies and despair, but also embrace the shadow as a sign of mystery yet unexplored. For in this balance lies wisdom: to walk in the light, but never forget the lessons carried by the shadow.