Hudson Institute

Where Science Ends and Religion Begins

Ron Dworkin on the Newton-Berkley Debate

Former Senior Fellow
 A drawing by Isaac Newton of his telescope next to a statue of him at the Royal Society in London, November 24, 2009 (Peter Macdiarmid/Getty Images)
A drawing by Isaac Newton of his telescope next to a statue of him at the Royal Society in London, November 24, 2009 (Peter Macdiarmid/Getty Images)

The last time someone found an error in Sir Isaac Newton’s work was in 1987, when a physics undergraduate showed that Newton, in his Principia, had mistakenly put the number “11” where he should have put “10.5.” The first time was in 1709, when Bishop George Berkeley published a criticism of Newton’s concept of absolute space. Although similar in the curiosity they evoked, the two mistakes differ in their import. The 1987 finding was an interesting aside. The 1709 finding was the first in a series of four errors, or questionable statements, that Berkeley uncovered in Newton’s work, and which had (and continue to have) the potential to change the balance of power between science and religion.

That potential goes untapped. Even people sympathetic to religion ignore it.1 Berkeley, for whom the University at California at Berkeley is named after, is mostly remembered today as the crank who denied the physical world’s existence. This is ridiculous; Berkeley did not say this. Nevertheless, it is how Berkeley is viewed in the academy, even among conservatives. A clergyman who foresaw the limits of science during the scientific revolution’s first stage, and who could compete with scientists on their own turf, remains overlooked.

Forty-three years younger than Newton, Berkeley studied philosophy and theology, eventually becoming Bishop of Cloyne in the Church of Ireland. In 1705, Berkeley and his friends at Trinity College, Dublin, formed a Society to investigate Newton’s philosophy. He eventually published his simple yet powerful criticism. It was the first of four problems he uncovered in Newton’s work, all of which have the potential to raise religion’s status relative to science for anyone bothering to listen.

The Error of Absolute Space and Motion

The story of Newton’s first error begins with Descartes, who declared all space to be occupied by some substance. True, Descartes admitted, that’s not how average people view space. When people throw a ball, they think the ball moves through empty air and lands in an empty space. But Descartes said average people were wrong. Motion is not an intrinsic quality of the moving object, he argued, but, rather, a changing of positions relative to other objects in its vicinity. Since space is never empty, such objects exist everywhere, he said.

Newton found a contradiction in Descartes’ relative idea of motion, then devised an alternative idea of motion so perfect that it occurs without relation to anything.  To demonstrate, he posited the idea of absolute space, or space without any bodies in it—in other words, empty space, which Descartes had declared impossible. Absolute space is not perceivable, Newton admitted. We live in relative space. But by supposing absolute space, Newton showed how a body moving in a straight line would continue moving in a line, and with no other bodies around it to relate to.

This is where Berkeley found Newton’s error. Berkeley said all motion is relative; absolute motion, on the other hand, is inconceivable. Because a reference point must exist from which to measure a moving body’s direction and speed, no motion can be determined in a body that exists alone in absolute space. Without a reference point, a body moving a thousand miles an hour would seem no different from a body standing still.

At the very least, a person must be watching the moving body, for how else would the body’s movement be perceived, Berkeley asked? The perceiver himself becomes the reference point, with the distance between the perceiver and the moving body measurable. Motion without a reference point or a perceiver is impossible, Berkeley said. “It is the purest idea of nothing,” he wrote.

Berkeley’s position was vindicated two centuries later in physicist Ernst Mach’s theory of relative motion. Mach’s work prefigures Einstein’s work on relativity. On science’s own turf, Berkeley was proven right.

Berkeley showed how science is sometimes built on mystery, just as religion is. Empirical science refutes the idea of God, calling God unreal, inconceivable, and without meaning, thereby putting all religion on shaky ground. Yet for two centuries, scientists believed in the unreal and inconceivable concepts of absolute motion and absolute space. Even after Einstein showed all motion to be relational, scientists continue to use Newtonian mechanics despite their shaky foundation. Scientists should use these mechanics, since they work. But all the while scientists piously shut their eyes to the fact that Newton’s foundational concepts are also inconceivable and without meaning. Indeed, Newton’s absolute space is supposedly eternal, infinite, indivisible, and immutable—just like God. If so, Berkeley mused, then why believe in absolute space but not in God?

The Error of Unperceived Qualities

During the seventeenth century, scholars wondered if some underlying substance in the universe called “matter” existed independent of the senses. Descartes believed matter did exist, and that, for example, a vortex of unknown particles pushed the planets around. Newton also flirted with the concept of matter. He saw light as something composed of obscure particles that exist beyond our senses in a universal medium he called “aether.” Newton continued along this line of thought in his theory of gravity. Unlike previous investigators, he wisely avoided trying to explain gravity’s cause and origin, and contented himself with simply describing the phenomenon mathematically, but inevitably he fell to speaking of unknown forces acting at a distance. Again he spoke of an “aetherial substance” to explain them.2

Berkeley called all of this ridiculous. Whether it was Descartes’ vortex or Newton’s “aether,” it was little more than dabbling in the occult and endowing fake substances with magical powers.3 Nothing exists if it cannot be perceived through the senses, or through machines that magnify the range of the senses, he argued. For example, a chair exists because it is seen and felt, and not because it is seen and felt—and existing. To be seen and felt is the definition of existence. To think something exists independent of the senses is a fantasy, he said.

In the case of “matter,” according to Berkeley, it was an inconceivable fantasy—an example of abstract thought run amok. Locke’s triangle was another example, Berkeley observed. The philosopher John Locke imagined a triangle that was neither oblique nor equilateral nor scalene, but all of these and none of these at once. Berkeley declared that such a triangle has never existed and can never exist, just like “matter.” By abstracting from real triangles, Locke had created a ludicrous concept.

According to Berkeley, when we imagine things we use data gathered from our senses as building blocks. When we imagine new triangles, for example, we rely on images of real triangles. When I practice anesthesiology and my patients hallucinate, they hallucinate using real sensory data they have gleaned from life. One patient of mine thought she saw a pink mouse running around in the operating room after surgery. An equilateral triangle, an oblique triangle, the color pink, and the figure of a mouse are all things perceived in real life; they are images of real things. The mind can play with these images to create new images. But whatever the mind creates with these images is potentially perceivable, like the original images themselves. Our minds cannot create something potentially unperceivable, such as Locke’s triangle, Newton’s “aether,” or so-called “matter.”

Even if one gives the unperceivable a name—for example, “Locke’s triangle”—the unperceivable remains as incomprehensible as before, Berkeley said. Naming something gets you nowhere. After all, Berkeley noted, the name “God” doesn’t make God any more comprehensible to human understanding, so why should scientific language applied to incomprehensible concepts work any differently?

Berkeley’s criticism is relevant today. Scientists think they move closer to understanding something if they name that something. For example, in my own field of anesthesiology the peculiar mental effects caused by the drug Ketamine is called “dissociative anesthesia.” The fact that anesthesiologists give this drug effect a name suggests they have an idea of how the drug works. In fact, they have no idea. Labeling the phenomenon accomplishes nothing. When asked about Ketamine, many anesthesiologists reflexively parrot the phrase “dissociative anesthesia” to sound smart, but besides that phrase they know little more than a layperson does about how the drug works.

The same prejudice lurks in physics. String theory postulates small one-dimensional objects called “strings” that supposedly form the basis of all interactions in the universe. Alternative dimensions and obscure, paradoxical particles are then created through the string theorist’s power of abstraction. The theorist then names these dimensions to make the unperceivable seem perceivable. Because they evoke no precise image and yet have a name, the theorist gets away with calling these abstractions real. But they are not real.

Neuroscientists who study consciousness do something similar. A neuroscientist working in consciousness studies once told me that to explain the mind we need a microscope sufficient to get us to the Planck level, or the lowest level of granular resolution, on the way to the infinite. At that level we will find the end of matter and the beginning of consciousness, he argued. It is also, he said with all due seriousness, where we will find God. “Does that mean God is near-granular?” I asked, tongue in cheek. He made no reply.

The point of my taunt was that neither God nor the mind is potentially perceivable to the senses, as Berkeley argued. Science, which deals with the perceivable, can never cross over into the realm of the unperceivable—certainly not by way of the scientist’s mind, which, as Berkeley observed, can only grasp the perceivable.  Scientists can go on subdividing beyond the practical limits of vision, but they cannot suppose the visible to be made up of elements by nature invisible. Scientists will never get beyond the brain to find the unperceivable mind.

Berkeley’s criticism also undercuts contemporary neuroscience’s so-called “cognitive-binding” theory. The eyes take in color, motion, and shape; the brain, according to neuroscience, supposedly binds these data to produce a unified picture. Neuroscientists assume the data are separable and in need of being bound. But, as Berkeley would say, how can they be separated? Is there a shape that lacks a color? Can something that moves lack a shape or a color? The answer is no. Color, motion, and shape are never separable.

My patient’s brain did not combine the color pink and the shape of a mouse so that her mind could see a pink mouse in the operating room. She saw a pink mouse from the outset. The color pink can never exist without a shape, and the shape of a mouse can never exist apart from a color. Moreover, her imagined mouse was racing around. According to cognitive-binding theory, “fastness” is combined in the brain with “pinkness” and “mousiness” to produce an image of a fast, pink mouse. But how can “fastness” exist without a mind to compare it with something stationary, and in that way judge it to be going fast? All motion is relational; it requires a mind to judge it, Berkeley observed. A brain cannot judge. Moreover, how can something be judged to be moving fast without being a “something” in the first place? And to be a “something,” wouldn’t that “something” have to possess a shape and color? Of course it would. The brain does not bind motion, color, and shape in preparation for serving them up to the mind as a single image. The mind sees the image whole.

Some neuroscientists claim that as consciousness fades, cognitive binding weakens and then disappears. Does this mean that as my patient fell asleep the image of the fast, pink mouse began to break up into its components of fastness, pinkness, and mousiness? The whole notion is ridiculous.

Neuroscientists who study consciousness work from a false premise that Berkeley identified three centuries ago. They think that “something we know not what,” some fundamental organizing principle of the mind, exists independent of the senses yet all the while remaining amenable to experimentation and theorizing. Berkeley showed this is impossible. The mind, like God, lies beyond our powers of sense perception, or even of our powers of imagination, since our imaginations use data gathered through the senses to form images. If something exists and is amenable to being sensed or imagined, it is perceivable and therefore neither mind nor God; if it is unperceivable, like mind or God, it is a waste of time trying to perceive it. Both science and religion have the same limits.

The Error of Cause and Effect

Newton described the universe as something clocklike, but it is wrong to think of him as a Deist. For Newton, God intervened in the world; the universe was more than just a wound-up watch left to run its course. Yet Newton did envision ironclad laws of cause and effect. This led him to muse on original causes, which led him to flirt with the occult—for example, the notion that the sun has both power and agency.

Newton’s error, argued Berkeley, was that he believed in material causes. He believed that objects had the power to “cause” events. For example, we think of fire “causing” smoke, or waves “causing” a ship to break up. Doing so is instinctual; when we look for causation we tend to look for things that move. But it is wrong to think of any material object as capable of causation, said Berkeley. Material objects are passive, not active. When object A leads to a change in object B, it is not a question of “causation” so much as a series of cue signs; it is a regular sequence of events. We see a giant wave coming; we expect the change coordinated with it—the smashing of the ship; the wave is a cause in the sense that it supplies a solid and reliable basis for prediction of what is going to happen; but the wave itself is passive and without the power to act. The wave is analogous to that of a policeman holding up his hand to stop traffic: the hand is not really the cause of traffic stopping; it is a cue sign telling us that traffic will likely stop in the next event.

Just as material objects are passive and incapable of causation, so are mental phenomena, argued Berkeley. Ideas, visual images, and memories may be in the mind, but they are not the mind. They are closer to material objects in that they are passive, not active. This is where confusion surrounding Berkeley’s philosophy often arises. Berkeley has been accused of saying that the physical world doesn’t exist, that everything exists only in the mind, and that nothing is real. What Berkeley actually said is that nothing in the physical world exists beyond what is potentially perceivable to the mind. Existence means to exist within the mind. When the mind perceives an object the mind is being active, yet the image of the object is passive and unable to “cause,” just like the object itself. In this respect, mental images inside the mind and objects in the physical world are equivalent. Both are passive. For Berkeley, only God and the mind are active and possess the power of cause.

I see Berkeley’s argument play out in the operating room. Once, during an awake brain operation, my patient had a seizure, with her brain lesion the likely source. Her seizure was a frantic explosion. Her brain was a frantic explosion. An atomic bomb is a frantic explosion. Yet none of these phenomena is active; they are all passive. They lack the power of cause. When the neurons in her brain lesion reached a certain state the next event was a seizure. They were a sign of the event to follow, just as split uranium atoms are a sign of the mushroom cloud to follow. But they were not the cause. They were like a cause in their significance; indeed, they were like causes in all but the causing, for they have no causal power, just as split uranium atoms have no causal power. True, explosive events follow, but neither the neuron nor the atom can make the tiniest change begin to be.

In the past, whenever I gave anesthesia to a patient undergoing brain surgery, I would often stare at the brain with a kind of reverence. I imagined the brain as different from all other organs because it “causes” the mind. Berkeley has corrected me. The brain, like the kidneys, lungs, and every other object in the universe, has no power of cause, just as the image of the patient’s brain in my mind has no power of cause. All are passive. I can see a patient’s brain, but that does not put me any nearer to a patient’s mind, for with my mind I cannot know a mind; my mind cannot produce a passive idea of a mind. It cannot produce a passive idea of what causes and acts, while the things I can see—the firing of neurons or the flow of blood through brain vessels—are just the coordinated movement of passive things.

Berkeley’s philosophy reveals the trap that neuroscience has fallen into. Many neuroscientists today think the brain somehow causes the mind. They spend their lives in a futile search for how. They are not totally to blame for their misguidedness; we are all victims of words. For example, every day we say the sun “rises” and “sets,” or that fire “heats” a pot. In doing so we get in the habit of attributing power to inanimate things. But some neuroscientists also have a vested interest in destroying Descartes’ paradigm that the mind and brain occupy separate universes, as the concept supports religion, and many neuroscientists dislike religion. For different reasons even Newton opposed Descartes’ model. He saw mind and brain as curiously mated and mingled, and that to think otherwise invited belief in ghosts and demons.

Ironically, Descartes, Newton, and today’s neuroscientists err along similar lines. Descartes says ideas, memories, and mental images are separate from the physical world. Newton and the neuroscientists say the mind is connected to the physical world. They are all wrong. As Berkeley observed, ideas, memories, and mental images are passive, like everything else in the physical world. Only the mind is active; only the mind perceives and produces images and ideas. The mind and its images are not the same. It is the mind, and not any psychic phenomena inside the mind, that is separate from the physical world. But the mind is separate from the physical world.

We cannot comprehend mind any more than we can comprehend God, Berkeley said. If we could, mind and God would be sensible, which would make them as passive as an ocean wave. Instead they are active, and therefore invisible to us, beyond the range of our senses or even our imaginations. An image of mind (or of God) in our minds is a passive picture of that which acts—and that is impossible. We know the mind’s active powers from within; we have linguistic conveniences that refer to the mind’s active powers; but that’s all we will ever have.

The Error of Infinity

When Newton invented his version of the calculus, he used the idea of “infinitesimals,” which he called “fluxions,” to explain it. The modern-day definition of fluxions is derivatives, or velocities at a moment, which have their own velocities of change, forming second derivatives, which have their own velocities, forming third derivatives, ad infinitum

Berkeley exposed an error in Newton’s calculus grounded in these fluxions. Berkeley did not dispute the truth of the results obtained through calculus. Instead, he showed that Newton’s calculus arrived at truth because of two compensating errors, which even mathematicians today admit. This allowed Berkeley to say that Newton’s calculus had created useful rules of thumb that yielded practical results but not a new science. Science is based on reason, and Newton’s calculus, based on fluxions, was based on mystery, according to Berkeley—no different from religion’s principles. Calculus worked, but how it worked and why it worked, no one could say for sure.

Berkeley grew interested in the calculus debate because he saw “infinitesimals” as a backdoor to Descartes’ “matter.” Newton’s fluxions supposedly grew smaller and smaller, until they grew infinitely small—like Descartes’ infinitely small particles. According to Berkeley there is no such thing as a particle infinitely small. Even the tiniest particle is finite; there cannot be quantities smaller than the minimum needed to be perceivable. The infinitely small fluxion, Berkeley joked, is nothing more than “the ghost of departed quantities.”

A finite quantity cannot have an infinite number of parts, Berkeley observed. To think otherwise is to fall into the grip of abstract general ideas. For example, we cannot see, touch, or imagine infinite parts in a finite line, but when we see a long line with a thousand parts, and then see a short line without a thousand parts, we are told to neglect the particular length of the short line—in other words, to abstract size from the line—and credit the short line with a thousand parts even though those parts are invisible. Once we believe in a thousand invisible parts in the short line it is easy to believe in ten thousand invisible parts, or an infinite number of parts, observed Berkeley. Legitimate representation passes into an illegitimate substitution.

Berkeley asked the scientists of his day, if you are willing to believe in infinity, why not believe in a divinity? Why stretch the imagination to believe in infinity but not in God? It was the same question Berkeley had posed in regard to absolute space. Both concepts are a form of religion under new guise. After all, what is the infinite other than the dark and empty waste, the moment when the beginning of all things and their end merge into one? What is absolute space other than the vast emptiness that surrounds the universe, stretching boundless, penetrating everywhere, disuniting everything, particle from particle?

Berkeley’s criticism forced later mathematicians to replace the concept of infinitesimals with the notion of approaching a limit. More important, he demonstrated that science, with its mysterious fluxions and ideas of infinity, has no monopoly on reason, while religion has no monopoly on mystery. Both enjoy a rough equivalence at their outer edges.

Berkeley Was Right

Like most people, Samuel Johnson wrongly assumed Berkeley denied the existence of the physical world, causing him to become a fierce critic of Berkeley’s philosophy. Boswell’s Life of Johnson recounts the story of how Johnson kicked a large stone—a testament to the physical world’s existence—and said, “I refute it [Berkeley’s theory] thus.” But the story is false. Johnson actually kicked the foundation stone of a church. This truth was concealed because of the unseemliness of Johnson striking a house of worship. Researchers at Yale who had access to Boswell’s original manuscript later exposed what really happened.4

The event symbolizes a larger truth about the relationship between religion and science: since the earliest days of the scientific revolution, and not because of Darwin’s theory of evolution or anything since, science and its enthusiasts have been hostile toward religion. Johnson mocked Berkeley with the same ferocity that religious people today are mocked. Indeed, Newton’s reputation flourished after his death not only because of his genius, but because his religious ideas were stripped away from his science and suppressed—so much so that when Newton’s religious writings came to light at public auction in 1936, much of the secular world was shocked. On the other hand, as religion’s unofficial representative on scientific matters, Berkeley was ridiculed from the start. When Kant claimed Berkeley denied existence outside the mind, elite opinion eagerly believed this mistaken interpretation. Organized science silenced Berkeley’s powerful criticism by dismissing it as harmless history and the ranting of a religious nut. 

With religion sidelined, things went along swimmingly for science for the next two centuries. Berkeley’s criticism only became relevant recently, when science pushed too far and hit a wall. So long as science confined itself to making useful gadgets, everything was fine. But science grew ambitious in the 20th century. In 1944, scientist Erwin Schrodinger urged science to tackle the problem of life. In 1994, scientist Francis Crick urged science to tackle the problem of the mind. In the second half of the 20th century, scientists working in string theory pushed to answer the question of the universe’s foundations. None of these ventures has proven successful.

In the case of neuroscience, the venture has sometimes proven nutty. Ironically, Berkeley, whom science calls nutty, anticipates what happened.

The study of consciousness has three factions. In the first faction are the materialists, such as Roger Penrose, who chase occult substances. They imagine “microtubules,” “quantum superpositions,” and “entangled states” as the basis for consciousness. They are like the Cartesians of yesteryear who believed in “matter,” and who chased “something they knew not what” that supposedly existed beyond the senses. They are like the Lockians who imagined an impossible triangle, then named that triangle, and by doing so thought the triangle real. Their concepts say nothing to anybody and remind nobody of anything.

In the second faction are the panpsychists, such as David Chalmers, who view consciousness and its contents (what they call “qualia”) as an autonomous realm separate from the brain. They are like the Cartesians who mistakenly confused the mind with its images. They are also like the Newtonians who wrongly believed the physical brain “causes” consciousness. Finally, like the medieval scholastics, they dabble in the occult, for they imagine consciousness to be a property of both animate and inanimate objects. They imagine, for example, that tables and chairs have some form of consciousness. This is science that has lost touch with reality.

In the third faction are the skeptics, such as Daniel Dennett, who view consciousness as an illusion. They say free will is an illusion, that what we see is an illusion, and that the brain plays tricks on us. Such skeptics have been around for centuries. As Berkeley observed, these people confuse illusions about sense data with illusory data. Of course we make mistakes in what we perceive—for example, in double vision. Of course there are illusions. But illusions are not false sensory data, Berkeley explained. They are true sensory data taken in the wrong way. My patient in the operating room mistakenly saw a pink mouse, but what she did see in her imagination she saw truly. Her delirious imagination was mixed up with true sensing; what she saw, she saw.

Science wants to define life, the universe, and the mind because it is on these three fronts that religion remains a serious competitor. In fact, science has no satisfying answer to give on these issues because it deliberately rules out of court the one answer that in reality is conclusive: Berkeley’s philosophy. Yet if science cannot succeed through logic and experimentation it will strive to do so through persuasion; it will become ideology. This is already happening on other fronts, as organized science makes pronouncements on everything from free trade to national borders. Science need only get people to believe that it is close to defining life, the mind, and the foundations of the universe for it to eliminate religion as a competitor.

The tactic is already working on the most basic level. Organized science has convinced many people that when they see, touch, and smell a rose, they really don’t. The rose is just an illusion, science says; or the mind is just an illusion; or the rose has consciousness beyond human understanding. Science says there is a real existence distinct from what people perceive, which is why people must trust to science and not to their own senses for guidance in everything from what a rose is to the meaning of existence to the values people should hold.

Berkeley showed us how to push back. As he would say, when we see a rose, we see what see. We touch what we touch. We feel what we feel. No illusions, no doubts, no intermediaries needed to interpret the experience for us or to direct our thoughts. How ironic that Berkeley, the religious figure, abstruse philosopher, and so-called nut, serves today as the defender of democracy, common sense, and the average person’s point of view.