Pascal's Wager (9 page)

In this sense, the seventeenth century was not that different from our own. Softer, more sympathetic Christianity, as represented by the Jesuits and the Molinists, produced an open, forgiving church that seemed to be edging toward a kind of relativism—“laxism,” as Arnauld and Pascal called it. This moral and spiritual relativism produced a backlash, a set of new spiritual movements within Christianity that insisted on dividing the world between the saved and the damned. This was just as true for Luther and Calvin in relation to the Renaissance church as it was for the Jansenists in the seventeenth-century church. An Augustinian backlash reformulated the church along Augustine’s harsher lines, lines that were more in tune with the uncertainties of the entire century. In a sense, these two versions of the faith could be typified today as “liberal” and “conservative.”

T
he story of the vacuum begins with Galileo. One spring day, he was watching the workmen pump water out of one of the cisterns on his property. He noticed that the suction pump that they were using worked well as long as the water was at a certain level, but that as soon as it fell below that level, the pump suddenly stopped working. Galileo called in a plumber to repair the pump, but the man told him that there was nothing wrong with it, for as everyone in the plumbing trade knew, no suction pump could raise water above eighteen
braccia
, or about ten and a half meters. Intrigued, Galileo studied the question for a time and then wrote about it in his
Two New Sciences
. He drew a distinction between a force pump and a suction pump, and noted that a force pump, which pushes the water from the bottom, could move the water much higher, depending upon the amount of force used, than a suction pump, and that a suction pump, which works by attraction, was limited in the height to which it could raise the water out of the cistern. He admitted that he was confused by this and was full of wonder, and then it hit him: in a suction pump, a vacuum was created above eighteen
braccia
.

This was quite a leap, because for nearly twenty-two hundred years Western culture had been following Aristotle and quoting his little maxim that “nature abhors a vacuum,” as if that explained it all. Almost everyone in the seventeenth century believed that it was impossible to create a void, a space empty of matter, because nature so radically preferred all space to be filled that it reacted violently to keep a vacuum from occurring. We must remember that Aristotle was an intensely earthbound man and that many of his odder dicta, like this one, came from his observations of nature. Greek philosophers had long held that like things tend to congregate together and that unlike things tend to repel one another. Thus, the idea of a force of gravity never occurred to them because they observed that heavy things tend to fall down and light things tend to go up. They didn’t need to pursue the matter further. The things that go down are mostly made of earth, and so they go to the place where earth is, and the same for water, while air and fire tended to rise to their natural places.
There were five elements: the four just mentioned—air, earth, fire, and water—that are natural to the earth; and the quintessence or fifth element, a particularly rarefied and perfect form of matter, which filled the heavens. The quintessence had the unique ability to execute perfect circular motions, like the motions of the heavenly spheres. Thus, there were two sets of laws in Aristotle’s physics, one for earth and one for the heavens, the earthbound laws applying up to the sphere of the moon, and the celestial laws applying beyond it.
²²

Nevertheless, Galileo’s experiments touched off a flurry of new questions and new experiments. If a vacuum could indeed be created in a glass cylinder, would the glass be completely empty of air or only partially empty? Just how empty was empty? And if it was truly empty, would sound be transmitted through it? Would light? In all of Galileo’s experiments, he didn’t notice that it got any darker in the cylinder with the creation of a vacuum. On the other hand, if sound could not be transmitted through the vacuum and light could be, then sound and light must be very different things indeed, which proved to be true in the end.

But in the seventeenth century, people were still wondering if a vacuum could be formed in truth, and if so, what kind of force would be needed to produce it. Evangelista Torricelli in Florence decided that the use of water columns was simply too unwieldy and began to use columns of mercury to run his experiments, which brought the whole thing down to scale for once. In 1642, he filled a glass tube with mercury and then stuck his thumb over the bottom of the tube and immersed the bottom end into a bowl of mercury, and then removed his thumb. The mercury fell seventy-six centimeters, rather than the ten and a half meters that a water column fell. From his experiments, he concluded that it was the weight of the atmosphere that caused the pressure to fill the vacuum, that we were all living at the bottom of a sea of air, and that the weight of all that air pressed on us so constantly that we didn’t notice it. Could it not be this weight, pushing on the surrounding surface of the water, that allowed a suction pump to work? Could it not be the weight of this ocean of air that raised the water to eighteen
braccia
and no more?

Torricelli discussed all this in a series of letters to a skeptical friend in Rome, Michelangelo Ricci, who defended the traditional view with a series of arguments, which Torricelli responded to. And in his responses, he laid out his entire idea. Parts of the contents of these letters eventually came to Père Mersenne by way of François du Verdus, a friend of Roberval’s who was living in Rome, though Verdus left out some of Ricci’s best objections and much about Torricelli’s belief that it was the weight of the sea of air that created the pressure. Mersenne re-created Torricelli’s experiments, and after visiting Torricelli in Florence and watching a demonstration of his experiments before a new cardinal in Rome, Giovanni-Carlo de’ Medici, he returned to Paris in 1645 and once again tried to re-create Torricelli’s experiment but couldn’t find enough high-quality glass tubes. A local engineer named Pierre Petit tried the experiment himself and failed, but then passed word of these experiments on to the Pascals, father and son, on his way through Rouen to Dieppe. And that brought the Pascals into the story.

It was 1646, and nearly everyone accepted Aristotle as the last word in the physical sciences. Étienne Pascal, however, was an exception. He was one of the few who had never accepted the Aristotelian cosmology and always thought that it would be possible to create a space devoid of matter if one followed the proper technique.
²³
After Petit’s visit, Étienne was excited about the possibility of repeating Torricelli’s experiment, and waited for his friend to return from Dieppe so that they could work on it together. Happily, they both lived in a city where there were plenty of first-class glassmakers, far better than those in Paris, and after Petit’s return they ordered a glass tube four feet long, with one end sealed, and slightly wider than a little finger. They then purchased fifty pounds of mercury, filled a bowl to three fingers, with two fingers of water on top, and then filled the tube with mercury. Petit stuck his finger over the open end and inserted it, finger and all, into the bowl of mercury until it touched the bottom. He checked to see if any air bubbles had slipped past him and settled at the top of the tube. Satisfied for the moment, he removed his finger, and
the level of mercury in the tube dropped over eighteen inches. Both men were amazed, and Petit, wondering if they had made a mistake, checked to see if air had gotten in somehow, but found nothing.

At that point, Blaise walked in and joined the conversation. He was skeptical at first and wondered aloud if air could get through the pores of the glass. Petit told him that if that were so, air would continue to penetrate and the level of mercury would go down as they were watching, but it did not. They then slowly raised the tube and were stunned to see that the empty space above the mercury grew larger as they raised it. The height of the mercury level in relation to the mercury in the bowl remained constant, however, until the bottom of the tube hit the level of the water, when all the mercury rushed out and water rushed in, right to the top. This proved that no air had gotten into the tube through the pores, because if it had, there would have been a bubble of air at the top when the water rushed in.

Nevertheless, while Étienne was nearly convinced, Petit remained cautious. Couldn’t air have gotten in somehow? Because Torricelli’s complete letters had not been transmitted to Mersenne, they did not know that the Florentine had already speculated that the vacuum was caused by the weight of the ocean of air, a notion that Blaise would discover later on his own. Even with his doubts in place, however, Petit set about demonstrating the experiment among his friends and acquaintances in Paris.

At this point, Blaise was twenty-three, a young man full of the energy of youth, an energy that all too often drained away in the middle of his work and left him sickly. His life alternated between rounds of intense scientific investigation and months of languishing in his bed from one of his many illnesses. By this point in his life, he was a slight fellow, with a biting humor and a rude manner, as if this spoiled son of a controlling father had never quite grown up. He could be tender; he could be kind; he could also be quite funny. But when he was on the trail of an idea, he was often unfair and pigheaded. What he lacked in size he made up for with a loud voice and an imperious manner. He was stubborn, hyperintelligent, with a terrible drive for perfection, a man who desperately wanted to wear the humility of Christ but could never quite pull it off. He spent
most of his adult life in controversy, both scientific and religious—a fact that surprised no one. Perhaps much of his personality can be explained by his health. He suffered from migraines nearly every day, and numerous other pains debilitated him. Nevertheless, he would make no excuses for himself and would fight on in spite of his illness. And no one could deny his cleverness. But he would need both his cleverness and his arrogance to defend himself during the coming great debate over the existence of the vacuum.

I
n the winter of 1646, Étienne Pascal slipped on an icy street in Rouen and fell, breaking his hip. According to Gilberte’s daughter Marguerite, he had been on his way to perform some charitable duty. At fifty-eight, he was no longer a young man, and given the state of seventeenth-century medicine, a broken hip could be very serious indeed. An injury like that required a specialist. But, luckily for Étienne, there were two professional bonesetters living in Rouen at the time: Monsieur Deslandes and Monsieur de La Bouteillerie. Étienne would not let anyone other than these men attend him, for he was convinced of their competence. It was a good choice, for the old man survived and was able to walk, though even he acknowledged later that he had come close to death.

The bonesetters were also pious gentlemen who between them had set up thirty beds for the care of the poor and indigent in their hospital. They treated the poor without charge and took on the job of teaching others their medical specialty without pay. But as guests of the Pascal household for over three months, they came not just to set bones, but to make converts. Needless to say, their influence over the Pascal family changed everything.

Until that time, the Pascals were pious but not fervent. As an
honnête homme
, a cultured gentleman of scientific and philosophical interests, Étienne lived his life by a code of rationality and honor, and suspected extremism in any form, especially the kind of antirational piety that he saw brewing in the Catholic revival, preferring to live his life as much by Michel de Montaigne as by Jesus Christ. Attending to his religious obligations as a matter of duty, he was more interested in intellectual discussions than he was in prayer. In a later century, he might well have been an agnostic.

Nevertheless, the Catholic revival was everywhere, like Christian Huygens’s “lumeniferous aether,” and in such an environment the most extreme forms of Catholic piety would often seem like heroism. One day, the pastor of their local church, once a member of Bérulle’s Oratory, in a fit of pious poverty renounced his benefice, his rights over the income of the parish, and put on the rough homespun of a hermit. Soon afterward, one of Étienne’s friends and colleagues, a fellow bureaucrat working for the king, told the Pascals quietly about his own conversion to reform Catholicism, and how it had changed his life. Everywhere Étienne turned, someone was getting religion.

The idea that his colleague had been converted from one kind of Catholicism to another, as if changing religions, was puzzling. It was a fairly new phenomenon, for the Catholic Church had always prided itself on its unity: didn’t the Apostles’ Creed call it “one, holy, catholic, and apostolic”? Catholicism had an immense capacity to contain within itself a wide variety of spiritual flavors, because in the past, whenever there was tension in the Body of Christ, the Catholic Church had spawned a new religious order. Protestants had changed that by their tendency to split
into ever-smaller denominations. In the seventeenth century, however, this Protestant tendency had leaked into Catholicism, so that movement from one group of the faithful to another, from a more secular variety of Catholicism to a more monastic one, became a secondary conversion, a translation from a debased Catholicism to the true faith—Augustinianism at its best. The Pascals found themselves surrounded by fervent Catholics, and by this new enthusiasm that boiled off the streets of Rouen like summer heat. As part of the unconverted, they were nearly heathen.

Then, in the nearby town of Rouville, an evangelical pastor came to town and preached the new piety at all the Masses. The priest’s name was Jean Guillebert, and he came equipped with a shiny new doctorate of theology from the Sorbonne. For years, he had followed the medieval tradition of taking a benefice from the parish without actually doing anything for the people and used the money to support his theological studies. But while at the Sorbonne, he had met the abbé de Saint-Cyran and picked up the new piety from him. From that day on, he became a priest in earnest. He actually moved back to his parish and started caring for the people.

This was the man who would convert the entire Pascal family. Apparently, his sermons were entertaining enough, for he drew crowds from all over Normandy. According to Gilberte, Guillebert was filled with an admirable piety and preached the finest sermons.

Now, however, closing the circuit, there were two young men sitting in the congregation in Rouville, taking in every word—two men who happened to be the bonesetters of Rouen, Monsieur Deslandes and Monsieur de La Bouteillerie. And when they arrived for their extended stay at the Pascal house behind the monastery of Saint-Ouen, they were on fire. In the quiet hours, they held long conversations with the family, and if Étienne was not ready to leap from his bed and run off to Rouville, Blaise certainly was. He read Saint-Cyran’s
Réformation de l’homme intéri-eur
(Reformation of the Interior Man) and was mesmerized. Perhaps he was looking for a spiritual life that was as challenging as his science. In the end, Blaise caught fire along with everyone else.

Who knows what people see in a belief that moves them? Whatever caused it, something clicked on in Blaise’s psyche, and from that point
on his heart went to war with his mind. There was much that troubled Blaise in Saint-Cyran’s book—as much as what excited him. In one passage, he read that Jansen believed that scientific curiosity was nothing more than another kind of sexual indulgence, and this agonized him. Suddenly, the thing that had given Blaise his identity, his greatest joy in a life of pain, had become a wickedness. How could he seek the salvation of his soul under these conditions? How much of himself would he have to give up? Everything, it seemed. A shadow fell on his spirit that would never lift.

Two strange attractors have emerged repeatedly in the long intellectual history of Catholicism; these two traditions, like gravity wells, have drawn adherents to themselves, becoming fashionable in their turn, white hot for a time, then cooling off like aging stars, only to be replaced by the other tradition. Those who seek to find God in all things, who have a general faith in reason, who believe that the world is a wide and good place and that people are reasonably decent, end up orbiting around the ideas of Thomas Aquinas (ideas known collectively as Thomism) and his Christian reclamation of Aristotle. Those who seek to find God outside human experiences, who distrust reason, who think that the world is a shipwreck and that people are no damn good, usually orbit around the ideas of Augustine. The more positive Thomism had no problem with Christians engaging in scientific study. Aquinas himself wrote his
Summa theologiae
in order to show that Christianity was not antirational, as opposed to the more advanced Aristotelian science of Islam. Perhaps it was a sign of the times, or perhaps it was an indicator of the younger Pascal’s quirky personality; in any case, he chose the one Catholic theological tradition most likely to set the two most important parts of his life into combat.

Blaise was then twenty-four years old. He was beyond the age at which a man strikes out on his own, but in the Pascal family such an action was unthinkable. Old Étienne had a plan for everyone, especially his only son. By that time, Blaise had done everything his father had expected of him; he had achieved preeminence in the scientific world that few had ever attained. His work on conic sections; his arithmetic machine, the Pascaline; and his experiments on the vacuum—these had made him famous. And
thanks to Marin Mersenne, Blaise’s name was known to the best minds in Europe. But all of this was according to his father’s plan. What part of his life was Blaise’s own? What part of himself was his? It was tragic that at this precise moment in his life, while seeking the truth of his soul, while brawling through that exquisite moment of vulnerability that young men wrap themselves in like a battle flag, he came upon the ideas of Cornelis Jansen and the abbé de Saint-Cyran.

Blaise continued his pious reading and from there plunged into works of theology, ever deeper into the writings of Jansen, Saint-Cyran, and Antoine Arnauld, who had become their great apologist, and bit by bit his conversion took hold. As Blaise was caught in his spiritual reading, he fretted about his life. He began to wonder if what he had been doing, his best accomplishments, was an act of supreme narcissism and a kind of attachment to the world. He had spent his entire young life spinning out variations on the strictest form of mathematical reasoning, and yet this very reasoning was now suspect. Mathematics was the most precise of the sciences and the one antidote Christian thinkers had in their arsenal to fight the skepticism that was rising like a fume from the
libertins érudits
. The seventeenth century was becoming an age of suspicion, because many of the old forms of reason were dying, and many thoughtful people, instead of trying to build up something new, wanted to tear everything down.

Then there were those, led by Descartes, who were casting about for something radically new to fill the gap. How could they build a new metaphysics that possessed both the certainty of mathematics and the scope of Aristotle? This was the question that Descartes was sure he had solved with his new method, one that cleverly wove in the very skepticism of the new thinkers and yet arrived at a new and more certain metaphysics for a new age. But even these attempts to shore up the dike of reason were being called into question.

Blaise, however, embraced the skepticism by acknowledging that human science, for all its power, was deeply flawed. He rejected Thomism and accepted Augustinian pessimism about human reason, perhaps because he was all too aware of the destructive power of sin. His whole life could be explained by that power. Sin and pain accounted for much of his
story: his childhood disease, his mother’s death, his father’s flight from Paris, the terrible peasant uprisings he saw all around him in Normandy, the poverty, and the disease. Had Adam not sinned, none of these things would have happened. When sin entered the world, it brought death along for the ride and, with death, disease. Here, perhaps, was a more satisfying explanation for the realities of the world than mathematics.

Much later, in his
Pensées
, he placed humankind on an open field between the angels and the animals, noble and wretched at the same time. Wretchedness was the product of sin and was constitutional, a part of human nature, whereas reason, also constitutional, was the product of God’s grace. But reason could plumb reality only so far, whereas wretchedness sank clear to the bone. The only way to understand the deep truths of life would be through the reasons of the heart, and not the reasons of the mind. We must make use of the nonrational parts of ourselves if we truly wish to understand. A mathematician he remained, but he never trusted mathematics the way Descartes did. In those three months, Blaise Pascal set himself on a course that would make him the great syncopation to the coming modern age, and for all his personal suffering, his writings lent depth and grace to the coming centuries. Years after his death, his ideas haunted the great minds—Voltaire especially, who despised Pascal’s trenchant Catholicism and yet could not deny the brilliance of his mind and the sweetness of his French.

And so, Blaise was converted, at least for the time being. His faith would wax and wane over the years. First, with the help of the bonesetters, he set to work on Jacqueline, whose faith would not wax and wane, and then the two of them set to work on Gilberte. Étienne remained skeptical, but slowly drifted in their direction. What was he to do? His children were his life, and whether he wanted them to or not, they had struck out on their own. All his adult life, he had been leading them; now they were leading him.

Still, Blaise was not entirely converted, not quite ready to give up his science. He had devoted too much of himself to it to do that. That would have to come a few years later, after the death of his father and after the night his heart was seared by divine fire.