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How the Church Has Changed the World: The Seeker of Harmony


"Gather round, lads," says the friar, stooping over an odd contraption, with a string fastened at one end, while the other end, laid over a wheel, is fastened to a freestanding weight.

Mersenne Marin Mersenne

In between are two frets, setting the length of the string to be plucked to make a musical note.

He plucks the string.  "D," says one of the boys.  They are dressed in the robes of novices.  This is a house of the Minims, the severe and simple order founded by Saint Francis of Paola.

"Absolute pitch!"  the friar laughs.  It's impossible not to like him.  He is blessed with a temperament that delights in everyone he meets — except for deists and pantheists, those pests.  Skeptics he can work with.

"Now what happens if I move the frets closer, to shorten the string by half?  Do you know?"

"Yes, Père Marin," says another novice, a mathematical amateur.  "It will be D again, but an octave higher."  The friar plucks the string, and the boys sing out D in falsetto, laughing.  "Pythagoras knew that," says the priest.  "But what happens if we move the frets back where they were, but double the weight that stretches the string?  What do you think, boys?"

They volunteer various guesses, some saying that the note should be an octave higher, others a third or a fourth, until the priest stops them.  "Lads, lads," he says, "you can't determine the answer by thinking about it.  The Lord made the world as he made it, freely, and we must learn from it.  We must not dictate to him how it should go.  So we do the test."

He plucks the string.

"Diabolus!"  cries the human pitch-pipe.

"Precisely," says the friar.  "G-sharp.  You see, I need the square of the weight to effect the octave.  Four times the weight, not twice.  Now what happens," he goes on, "if I keep the tension and the length the same, but use a string four times as thick?  The sound will be lower, eh?  Think of guitars.  How much lower?"

"We must do the test," say the boys.

"We must do the test," says the priest, Marin Mersenne, father of the science of acoustics.  "Never try to think in a vacuum," he says.  "The good Lord made the world in measure, number, and weight, for us to behold and study in gratitude.  What sound will this string make in a vacuum?  None at all.  The air is all around us, like water, and when the string vibrates, it's like a stone you toss into a pond, and the ripples in the air reach your ear."  At which the bells ring for Prime.

Universal harmony

Marin Mersenne (1588–1648) was always fascinated by what made for harmony, how sounds are caused and how we experience them.  He's the first man I am aware of to study the human vocal cords, the epiglottis, and the oral cavity as a musical instrument.  He asks and tries to answer hundreds of questions about music.  What happens to the sound when we change the material of the thing that vibrates?  Why do we find pleasing the movement from unison to the major third (C, for example, to E), but not the movement from the major third to unison (E to the C above it)?  How can we tune a keyboard so that we will hear the notes in concord with one another, regardless of the key we play in?  If you play the piano, you are in debt to Mersenne.

Mersenne knew that Plato and his followers believed that music, with its approach to the immaterial, could raise the mind of man to the contemplation of God.  For all his scientific investigation into the physics of sound, Mersenne believed it too.  "If everything in the world," he wrote, "serves to raise us by degrees to God, the dependence of light upon luminous bodies, and of sound upon air, does not stand on the lowest rung.  For these things should remind us of how we depend upon God, because neither of them is its own cause or its own subject."

The harmony of truths found in Mersenne an energetic investigator.  In those days, the Christian faith was attacked on one side by deists, who reduced God to the world he created, and on the other by skeptics, who said that man could affirm nothing with certainty.  Mersenne wrote against both, in an enormous compendium on the first six chapters of Genesis.  "Music bears its own creed," he says, "for is it not God, as from the inexhaustible ocean of his delight, who pours forth upon us this small pleasure?"

A Fellowship of Christians and scientists

For Father Mersenne, to ask about the world was to give thanks to God.  We can see such Christian humility in his tireless and selfless friendships with more than a hundred of the great thinkers and scientists of his time.  René Descartes was a timid hypochondriac, but Mersenne encouraged him, introduced him to others, and posed questions to him to sharpen his thought and to keep him on the sunny side of the faith.  Galileo was a difficult man, but Mersenne sought him out, defended his research among other churchmen, and collaborated with him on mathematical problems.  The most important of these involved the cycloid, the shape that a point on a wheel traces as the wheel rolls forward.  It is no idle curiosity.  What's the shape of the incline that makes an object go forward the fastest, given the laws of gravity?  It isn't a diagonal.  It's the cycloid, upside down.  Mersenne's work helped another of his correspondents, Christian Huygens, to invent the pendulum clock.

The Church took the lead in every path of research into every field. She was the nerve center, as wonder before God and his creation was the inspiring breath.

From 1633 on, an academy of scientists formed itself in Paris, centered upon the person and the energy of Marin Mersenne.  His knowledge was encyclopedic.  He knew more of physics than did any but the best.  He knew more of mathematics than did any but the best; and so forth with other fields of knowledge.  That allowed him, since he had not a trace of envy in him, to put people and their works together.  Nowadays, if you want to know who is doing work on prime numbers, you search online.  In those days, you asked Father Mersenne, and he would send you the books he had, or put you in touch with the men themselves.

The academy met on Thursdays, and Mersenne took the lead, suggesting questions to the others; and Mersenne's questions were often more fruitful than other people's answers.  He too worked on all kinds of things.  One of them was to find a prime number higher than any previously known.  (A prime number has no factors but itself and 1; 7, 11, and 13 are prime, for example.) Mersenne suggested a series of what are called Mersenne Primes, of the form 2n–1, for some integer n>0.  He claimed that 2127–1 and 2257–1 were prime.  He was wrong about the latter, but correct about the former, which was for a long time the largest prime known (the seven largest primes currently known are all Mersenne primes).  The field remains a great one for number theorists, cryptographers, and programmers.

Scaling the heights

What little do many today know about the Church and the advancement of human knowledge!  At best they concede that there were a few scientists who happened to be faithful believers, with even a few priests here and there.  They do not know that the Church took the lead in every path of research into every field.  She was the nerve center, as wonder before God and his creation was the inspiring breath.

We can see as much when Father Mersenne went to Italy in 1644 to meet the young prodigy Evangelista Torricelli.  The latter, educated by the Jesuits, had been sent to Rome at age eighteen by his uncle, a Camaldolese monk, to study the sciences.  Torricelli had performed an important experiment on the weight of air — a matter that Blaise Pascal, who would also be welcomed into Mersenne's circle, would settle.  Why can you use suction to bring water to a height of thirty-two feet, but no higher?  To answer the question, Torricelli invented the mercury barometer, and Mersenne and he conducted a famous experiment, taking the barometer up a high mountain and noting the difference in the air pressure at the top.  If you live in Denver, you know the air is thin.  It was the young Italian and the French friar who first proved that air pressure decreases at higher altitudes.

But the truest heights for the good Christian friar were always those of wonder and thanksgiving for the gifts of God: first that man made in God's image should exist at all, and then that this same man, fallen into sin, should be redeemed and made new.  For man, wrote Mersenne, was "testimony to the infinite wisdom of God, a most perfect work, indeed the aim of the world, its center, the embracer of all," a true cosmos in miniature.  "O blessed man," said he, meditating on what it meant for Adam to be made in the image of God, "whom mercy watches over, truth instructs, justice governs, and peace fosters!"  Mersenne can hardly contain his joy, to think that God "has pursued me with such love, me a worm, me a nothing, and prepared this universe for me as if for an emperor!"

Is that not motive enough to seek out the secrets of the world around us?

This is J. Fraser Field, Founder of CERC. I hope you appreciated this piece. We curate these articles especially for believers like you.

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Magnificat Anthony Esolen. "How the Church Has Changed the World: The Seeker of Harmony." Magnificat (July 2021).

Reprinted with permission from Magnificat. Image credit: Public domain, via Wikimedia Commons.

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The Author


Anthony Esolen is writer-in-residence at Magdalen College of the Liberal Arts and serves on the Catholic Resource Education Center's advisory board. His newest book is "No Apologies: Why Civilization Depends on the Strength of Men." You can read his new Substack magazine at Word and Song, which in addition to free content will have podcasts and poetry readings for subscribers.

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