Leonardo Fibonacci, the great 13th century Italian mathematician

“Leonardo Fibonacci, the great 13th century Italian mathematician (1175–1250) created the ‘Fibonacci sequence’ to explain behavior in nature mathematically. History has it that the first question he posed was how many rabbits would be created in one year starting with one pair.” – Rick Santelli

In this reflection, Rick Santelli recalls one of the most wondrous intersections of mathematics and nature, a moment when human reason caught a glimpse of the divine order woven through creation. He speaks of Leonardo Fibonacci, the man who, in the 13th century, first revealed a sequence that would become one of the most profound discoveries in all human thought — a pattern that breathes through the veins of life itself. What began as a humble question — “How many rabbits would be created in one year, starting with one pair?” — unfolded into a revelation that showed how numbers could describe the growth of life, the spiral of shells, the unfolding of petals, and even the rhythm of galaxies. In this simple riddle of reproduction, Fibonacci had unveiled a truth that nature had whispered since the dawn of time.

The origin of this quote and its subject lies in Fibonacci’s famous problem from his book Liber Abaci (The Book of Calculation), written in 1202. In an age when Europe was still awakening from the slumber of the Dark Ages, Fibonacci brought to the West the knowledge of Arabic numerals, algebraic reasoning, and mathematical logic from the East. Among his many examples, he posed a seemingly trivial puzzle — how fast might a population of rabbits multiply if each pair gave birth to another every month, and those new pairs did the same in turn? From this, he discovered a sequence of growth where each number is the sum of the two preceding it: 1, 1, 2, 3, 5, 8, 13, 21... Thus, he revealed a pattern of natural expansion, an elegant law that governs not only rabbits, but the growth of living things and the balance of the cosmos itself.

What makes this story powerful is not merely the numbers themselves, but what they represent. Fibonacci’s sequence is a symbol of order arising from simplicity, of life emerging through pattern, of beauty hidden within logic. The same numbers that describe the birth of rabbits also appear in the spirals of seashells, in the pattern of sunflower seeds, in the arrangement of pinecones, and even in the proportions of the human face. Each spiral, each curve, each repetition is a reflection of harmony — a quiet declaration that the universe, though vast and complex, is built upon laws of unity. Fibonacci’s discovery thus bridges the gap between mathematics and the divine, between reason and wonder, showing that science does not destroy mystery but deepens it.

Throughout history, the Fibonacci sequence has been rediscovered in art, architecture, and music. The Greeks called it the Golden Ratio, the divine proportion that guided the design of temples and sculptures. Renaissance masters like Leonardo da Vinci found it in the human form, using it to shape the geometry of beauty in works like The Vitruvian Man. Even the spiral of galaxies echoes this pattern, suggesting that what Fibonacci observed in a thought experiment about rabbits was in fact the universal language of creation. In every age, this sequence has whispered the same truth — that the universe grows by harmony, and that within the chaos of life there lies an invisible order, waiting to be perceived by those who look deeply enough.

And yet, there is also a moral truth in Fibonacci’s discovery. For what is mathematics but the art of understanding growth, of tracing how one step leads to another, how today builds upon yesterday? The Fibonacci sequence teaches us that every number, every moment, depends on the ones that came before — that life itself is built on continuity and connection. Each decision we make, each action we take, becomes the foundation for the next. As the numbers build toward infinity, so too does human knowledge, each generation adding to the wisdom of the last. Fibonacci’s question about rabbits becomes, in this way, a metaphor for human progress — the endless multiplication of understanding, born from curiosity and carried forward by those who dare to ask why.

Consider how this pattern echoes in the story of civilization itself. The seed of one idea — whether in science, art, or morality — often gives rise to many others, just as one pair of rabbits gives rise to a field. From Fibonacci’s simple equation came the mathematics of growth, the study of biology, the design of architecture, and even the calculations behind modern finance and technology. Every discovery, like every number in his sequence, is born from the union of what came before. The past and the present combine to create the future — and so long as curiosity survives, the sequence continues, ever expanding toward the infinite.

And thus, my listener, the lesson of Fibonacci is not only mathematical — it is spiritual. From a question of rabbits, he revealed the sacred truth that creation itself is mathematical, yet alive. That every act of growth — whether of a tree, a thought, or a civilization — follows the same rhythm of addition, balance, and harmony. The wise, therefore, must learn to see the patterns within life: to recognize how actions connect, how small beginnings lead to great ends, and how simplicity often conceals grandeur. For the universe speaks in numbers, and those numbers speak of unity — that all things are part of one unfolding pattern, both finite and eternal.

So, remember this, child of reason and wonder: when next you see a spiral in a shell, a sunflower, or a storm, see in it the legacy of Leonardo Fibonacci, who taught us that mathematics is not merely calculation, but revelation. Seek the harmony in the world, and in your own heart — for in understanding how life adds and multiplies, you will see that even the smallest act, like the first pair of rabbits, may give rise to infinite creation.