God and the Folly of Faith: The Incompatibility of Science and Religion (11 page)

Perhaps the most significant new conception here, contributed to by both Ptolemy and Copernicus, was that Aristotle was wrong to use philosophical reasoning to determine the nature of reality. Rather, one must make careful observations and then fit these observations to mathematical models. Theological considerations, such as apparent contradictions with the Bible, are to be considered separate from science. In the sixteenth-century perspective, however, God was still behind everything and was still needed as an ingredient of any scientific theory.

The revolutionary development in human thinking that we call the new science was punctuated by Johannes Kepler (died 1600). Having available the comprehensive data from the precise nontelescopic observations of Tycho Brahe (died 1601), Kepler discovered that the motion of the planets could be beautifully described by elliptical orbits with the sun at one of the two foci of each ellipse. When Newton proved that elliptical motion followed from his laws of motion and gravity, and his friend Edmond Halley (died 1742) used those laws to successfully predict the reappearance of the comet that bears his name seventy-six years later, well after his and Newton's deaths, the scientific method became triumphant. Everything in the history of science since then has been epilogue.

The eventual conquest of observation as the final arbiter of scientific truth had begun in earnest with Francis Bacon (died 1626). Bacon, an English lawyer, was an important Parliamentarian and aristocrat during the reigns of Elizabeth I and her successor James I. Bacon rose as high as Lord Chancellor before falling from power.

Bacon initiated the eventual discrediting of Aristotle's scientific methodology, in which knowledge is obtained primarily by reason and reference to authority. Bacon introduced the part of the method of scientific inquiry whereby we start with observations and use inductive reasoning to arrive at underlying principles. True to his beliefs, he died from pneumonia obtained while studying freezing as a means for preserving meat.

Barbour observes that Bacon neglected the theoretical side of science and
omitted the role of creative imagination. He gives as an example of such creativity Galileo considering the motion of a body without air resistance, a conception we do not experience (or at least did not at the time of Galileo). I would add Galileo's notion of unaccelerated motion, which was not a common experience riding in a horse-drawn carriage on a cobblestone street. We will get to Galileo in a moment.

But first, let us mention another important figure who helped set the stage for the scientific revolution, René Descartes (died 1650). His Cartesian coordinate system and analytic geometry became basic tools that are still used in physics. He was able to reconcile God with the new mechanistic science that was just starting to develop, with his help, by making a clear distinction between body and soul, or, as we would now put it, matter and mind.

Prior to the seventeenth century, it was universally believed that the movements of bodies were the result of spiritual action, with God as the prime mover, as taught by Aristotle and Aquinas. Descartes replaced
spiritual
causality with
mechanical
causality, in which inanimate bodies and animals were machines moved around by natural forces. The one exception was the human being.

Descartes proposed that humans possess a distinct immaterial, immortal mind, or soul, that controls their movements. This duality became a fundamental ingredient of Christianity, as well as fitting in well with just about every other religious belief in the world. And it is a major place where religion and modern science, as I will later argue in detail, irreconcilably disagree.

Finally, let us discuss another thinker of the seventeenth century who has had some influence on modern thought, although he was largely disputed or ignored in his lifetime. This is the Jewish, Dutch philosopher Baruch Spinoza (died 1677).

Spinoza formulated the doctrine known as pantheism, mentioned above, that associates god with an impersonal cosmic order. When a rabbi asked Einstein if he believed in God, the great physicist was able to escape disapproval by saying he believed in “Spinoza's god.” The rabbi may have been unaware that Spinoza had been excommunicated (a rare event in Judaism) from his synagogue in Amsterdam for his teachings. The Catholic Church banned all of Spinoza's books, and many were burned by Protestant reformers.

Einstein and many other avowed atheistic physicists of our era, notably
the celebrated cosmologist Stephen Hawking, use the term “god” metaphorically in the Spinozan sense, to the enormous confusion of laypeople who have never heard of Spinoza or of pantheism and are thereby led to falsely think that Einstein was, and Hawking is, a believer. It would be better for all if nonbelieving scientists avoided using this metaphor. More recently, Hawking called heaven a “fairy story.”
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GALILEO

Galileo is generally recognized as the first true scientist of the new science because he placed observation over authority except on purely theological matters. As we have seen, several Islamic scholars had done the same, so Galileo was not the first to emphasize the importance of observations. But he took the ball and ran with it.

The Florentine scholar improved the previously invented telescope, increasing its magnification factor from three to twenty, and turned it on the heavens. He observed four satellites of Jupiter and inferred that they rotated around that planet rather than around Earth, providing support for Copernicus's heliocentric conjecture. He saw sunspots and mountains on the moon, rejecting the common belief that the celestial bodies, being part of heaven, were perfect spheres.

By watching a swinging lamp in church, Galileo deduced the principle that the period of a simple pendulum depends only on its length. He noted that all heavy objects fall with the same acceleration, neglecting air resistance.

He was the first to make a careful distinction between velocity, the rate of change of position, and acceleration—the rate of change of velocity. When asked the reasonable question, “If the Earth moves, why do we not notice it?” Galileo gave two responses. First, he insisted that his observations of celestial bodies provided evidence that Earth moves and thus our intuition that we can detect our motion must be wrong. Second, he explained that when we sense our motion we are observing our acceleration, not our velocity. This has become known as the
principle of Galilean relativity:
velocity is relative. There is no such thing as absolute motion.

When we measure the velocity of an object, it is always with respect to some particular observer's “frame of reference.” For example, suppose I watch you drive by in a car and measure the car's velocity to be 80 kilometers per hour. This is the velocity of the car with respect to my frame of reference. However, you are sitting in the car, so the car is at rest, zero speed, in your frame of reference.

The story of Galileo's conflict with the Catholic Church is widely known and also widely misunderstood. Many authors who agree with me that science and religion are incompatible have used the Galileo affair as a prime example. I expect some readers will expect me to take the same approach. However, I must bow to the more expert conclusions of most contemporary historians that the story is more complicated and that Galileo brought much of his trouble on himself.

Not that Church authorities were blameless, but the facts are that Galileo's crime was not so much his teaching that Earth moved about the sun; his crime was more about disobedience. This was before free speech was accepted as a basic human right. In 1616, Galileo had been ordered to cease teaching the Copernican picture as a true representation of reality. He was instructed to instead teach it only as a convenient mathematical formalism. This was not unreasonable, because the strongest evidence in support of the Copernican model, such as the moons of Jupiter and the imperfection of the celestial bodies, had not yet been observed.

In 1632, Galileo published
Dialogue on the Two Chief World Systems
, in which he argued that the tides provide evidence, incorrectly as it turned out, that Earth moves. Worse, Galileo used a foolish character, foolishly named Simplicio, to express some arguments that had been advanced by Pope Urban VIII, a longtime friend and supporter of Galileo. The pope must have said, “We are not pleased.”

Although the Inquisition had worked out what we today call a “plea agreement” that would have left Galileo with little more than a slap on the wrist, the Pope intervened in his case, and in 1633 Galileo was tried by the Inquisition, found guilty, and sentenced to house arrest. Although he was forbidden to write further, his
Discourse on the Two New Sciences
, which laid the foundation of mechanics that would be built upon by Newton, was published in Holland in 1638.

The Catholic Church was, in fact, almost ready to adopt the Copernican model, as better observations began to show the model's superiority as a calculational tool—a fact that was not immediately evident in Copernicus's time. As we have seen, both Islam and Christianity relied on astronomy to determine important dates in their religious calendars, so the Church was happy to have a better method.

However, with the Protestant Reformation, the Church backed off from its flexibility on cosmology, feeling pressure to maintain its traditional conservative doctrines.
Dialogue
was placed on the Church's prohibited list and not removed until 1822. In 1992, a commission appointed by Pope John Paul II acknowledged, “Church officials had erred in condemning Galileo.”
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Martin Luther (died 1546) opposed the Copernican model because it contradicted the Bible. The other great reformer, John Calvin (died 1564), is often quoted as saying, “Who will venture to place the authority of Copernicus above that of the Holy Spirit?” However, this quotation had not been found in any of Calvin's work, and it is not clear what Calvin's position was on the new astronomy.
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As the Reformation developed, Protestant countries, notably England, became more intellectually free than Catholic countries and provided the environment for Newton and others to proceed with a revolution in human thought. After all, the Reformation demonstrated that authority could be questioned, even the authority of the Roman Church, which was claimed to follow in an unbroken chain from Peter, Christ's first Vicar of God. Surely it is no coincidence that Luther and Calvin were contemporaries of Copernicus.

Galileo always insisted that his teachings did not conflict with those of the Church. He is often quoted as saying, “The Holy Spirit's intention is to teach us how one goes to heaven, not how the heavens go,” although it is generally assumed that he was in turn quoting Cardinal Cesare Baronius (died 1607). The new science opened the door to what is known as
natural theology
, in which God's majesty is revealed through the wonders of nature. It also led to deism, which reached full flower briefly in the eighteenth century during the brief period known as the Enlightenment, or the Age of Reason. In Enlightenment deism, an impersonal creator sets the universe in motion and interferes no further with it as it proceeds deterministically according to the laws of mechanics set down by the creator.

The new cosmology removed humanity from the center of the universe and challenged the teachings of both Aristotle and the Church. Still, in the medieval view humans were special in that they had not only a material body but also an immaterial soul.

As for the Galileo affair, historian Thomas Dixon says it was not a clash between science and religion, as it is usually remembered, but rather a dispute about who was authorized to produce and disseminate knowledge. Galileo's claim that a sole individual could arrive at knowledge by his own observations and reasoning was considered presumptuous and a direct threat to the authority of the Church.
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Moreover, Galileo promoted a philosophical view now defined as
scientific realism
, which has become the dominant perspective of most scientists ever since. According to this doctrine, scientific observations and inferences about the unobserved represent a true glimpse of ultimate reality. Galileo insisted that Earth really moved around the sun.

The Church did not object to scientific models such as those of Copernicus and Kepler as being useful tools. But it insisted that science was just in the business of making predictions of observable phenomena and that one should leave questions of ultimate truth to be determined by scripture as interpreted through the revelations and traditions of the Church.
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The Catholic Church would have been perfectly happy if Galileo had, like earlier astronomers, just followed the lead of the Lutheran theologian, Andreas Osiander (died 1552), who oversaw the publication of
De Revolutionibus Orbium Coelestium
(
On the Revolutions of the Heavenly Spheres
) and added an unsigned preface that said:

It is the duty of an astronomer to compose the history of the celestial motions through careful and expert study. Then he must conceive and devise the causes of these motions or hypotheses about them. Since he cannot in any way attain to the true causes, he will adopt whatever suppositions enable the motions to be computed correctly from the principles of geometry for the future as well as the past…. These hypotheses need not be true nor even probable. On the contrary, if they provide a calculus consistent with the observations, that is enough.
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This is what we call
instrumentalism
. Today, scientific realism is the common belief among most scientists—not because they have thought about it but because they would rather not. Philosophers of science, however, have made a convincing case that our scientific models and their ingredients—while not arbitrary, culturally dependent narratives, as claimed by postmodernists—are formulated with a great deal of subjectivity and need not precisely describe “true reality.”