The Miraculous from the Material: Understanding the Wonders of Nature

Introduction

I call myself a spiritual materialist. By materialist, I mean that I believe the world is made of material stuff, and nothing more, and that material obeys rules and laws. At the same time, like many of us, I have spiritual experiences: feelings of connection to other human beings and to the larger cosmos, moments of communion with wild animals, the appreciation of beauty, wonder. Nature is capable of extraordinary phenomena. We human beings stand in awe of those phenomena. That’s part of my view of spirituality.

I became a materialist early in life. Around the age of twelve or thirteen, I installed a laboratory in a large closet off my second-floor bedroom. There, I collected little bottles of various chemicals like potassium and molybdenum and sulfuric acid, petri dishes and test tubes, beautiful glass beakers and boiling flasks, Bunsen burners, motors of different kinds, a microscope and glass slides, resistors and capacitors, batteries, photoelectric cells, coils of wire of varying thicknesses and grades, delicate pipettes, filters and crucibles, voltmeters and ohmmeters, scales, pressure gauges, and random devices I’d found in the discard pile of an electrical supply store. It was in that homemade lab that I began my investigations of the material world.

I loved to build things. I read in Popular Science or some other magazine that the time for a pendulum to make a complete swing, called its period, is proportional to the square root of the length of the pendulum. What a fascinating rule! But I had to see if it was true. With string and a fishing weight for the bob at the end of the string, I constructed pendulums of various sizes. I measured their lengths with a ruler and timed their periods with a stopwatch. The rule was true. And it worked every time, without exception. Using the rule I had verified, I could even predict the periods of new pendulums even before I built them. Evidently, the physical world, or at least this little corner of it, obeyed reliable, logical, quantitative laws.

In high school, in collaboration with a friend, I built a light-borne communication device. The heart of the thing was a mouthpiece made out of the lid of a shoe polish can with the flat section of a balloon stretched tightly across it. Onto this rubber membrane we attached a tiny piece of silvered glass, which acted as a mirror. A light beam was focused onto the tiny mirror and reflected from it. When a person talked into the mouthpiece, the rubber vibrated. In turn, the tiny mirror quivered, and those minute quiverings produced a shimmering in the reflected beam, like the shimmering of sunlight reflected from a trembling lake. In this manner, the information in the speaker’s voice was precisely encoded into light, each rise and dip of uttered sound translating into a brightening or dimming of the beam. After its reflection, the fluttering ray of light traveled across the room to our receiver, which we built from largely off-the-shelf stuff: a photocell to convert varying intensities of light into varying intensities of electrical current, an amplifier, and a microphone to convert electrical current into sound. Finally, the original voice was reproduced at the other end. Looking back on this project decades later, I still regard the contraption as miraculous. Yet I knew exactly how it worked. I had put it together piece by piece. (In college, I also learned how photocells and microphones work.) As with my pendulums, here was evidence that mechanism and cause underlay the workings of the world. There was no need to invoke magic or the supernatural or any nonmaterial essence to explain earthly phenomena. The physical world was miraculous all on its own.

At the same time I was forming these materialist views of the cosmos, I also observed some amazing spectacles. With my microscope, I discovered an entire world, invisible to the naked eye. In a thimbleful of water from a nearby pond, I saw tiny creatures wriggling and gliding about, shaped like ellipses with little waving hairs. Paramecia. I saw roundish blobs, pulsating with smaller blobs inside them. I saw other minuscule organisms, hundreds of times smaller than a grain of sand, gyrating, turning, throbbing, sporting about.

Our family took vacations near Kentucky Lake, about 175 miles northeast of Memphis, where I grew up. Many mornings, if I rose early, I could see a mist hanging low over the lake. Ambers and lavenders and mossy green hues would refract in the air for an hour, then melt away like some rare species of plant in bloom for only a few hours.

In college, I had my first look through a good telescope and saw the rings of Saturn. Anyone who hasn’t seen them should. They are perfect circles. They are so perfect and pure that you think they couldn’t be real. You think that nothing in nature could attain such perfection. And yet there they were, almost a billion miles away, austere, cold, and crisp, floating in silent perfection.

Understanding the material and scientific underpinnings of these spectacular phenomena hasn’t diminished my awe and amazement one iota. So I don’t believe in miracles, but I do believe in the miraculous. The miraculous abounds, and the material world and its laws are quite enough to explain it. And that too is miraculous.

Atmosphere

Many years ago, I had a conversation with former astronaut Jeffrey Hoffman, who made five trips aboard the space shuttle from the mid-1980s to the mid-1990s. What I will never forget was his description of the Earth as seen from space. He said that the atmosphere looked like a thin, blue ribbon encircling the planet. Exactly the same words were used by former astronaut Piers Sellers, in an interview in 2016: You get up there, and the Earth is this huge ball. And when you look at the horizon, there’s this tiny film of gas around it. It’s just a thin, blue ribbon. It’s the atmosphere. I mean, there’s almost nothing there.

The U.S. satellite Explorer 6 captured the first photograph of Earth from space, in 1959. But it was a black and white photo. Not until a couple of decades later did we technological creatures capture the first color photos of our planet, showing the blue atmosphere.

We take the air around us for granted, like night and day. But in fact, we wouldn’t exist without it. There are other, less obvious roles played by our atmosphere. Its upper layers absorb harmful ultraviolet light from the Sun. Ultraviolet light can cause cancer, blindness, and other serious health problems. Our atmosphere also acts as a blanket, holding in the heat radiated by the ground and keeping us warm. Without an atmosphere, the temperature of the Earth would be far below freezing, about 8 degrees Fahrenheit. One other unpleasant item: the oceans and all surface water would boil away without the pressure of the atmosphere.

But getting back to the thin, blue ribbon. Why is it blue? And why is it thin? The atmosphere is blue because blue wavelengths of light are scattered by the molecules of air to a greater degree than red wavelengths of light. As explained in the essay Rainbows, sunlight consists of a range of colors that blend together to make white light. Each color corresponds to a different wavelength. (Light consists of traveling waves of energy, with troughs and crests, like waves in water. The distance between successive crests is called the wavelength.) The shorter wavelengths, toward the blue end of the spectrum, interact with air molecules more strongly than the longer wavelengths, toward the red end of the spectrum, and get scattered about from one molecule to the next, eventually moving in all directions. That’s why we can see daylight even when not looking directly at the Sun.

While the atmosphere covers the entire Earth, when we photograph the Earth from space, we look through much more atmosphere in the direction of the edge of the Earth than in the vertical direction, straight down. Similarly, on a foggy day the fog appears much thicker when looking sideways, parallel to the ground, than when looking vertically up. Because of these simple geometrical effects, we see a blue ribbon encircling the Earth rather than a spherical shell surrounding it.

What determines the thickness of the atmosphere? Temperature, gravity, and the types of molecules. The molecules of Earth’s atmosphere—oxygen, nitrogen, carbon dioxide, and water vapor—are zigzagging around, like all molecules in a gas. Their motions in the vertical direction can reach only so high before the Earth’s gravity pulls them back, like balls thrown upward. The maximum height they can reach is determined by the strength of the Earth’s gravity and by their average speed, which in turn is determined by the temperature of the air. (The higher the temperature, the faster the average speed.) Given these factors, the maximum height of most of the air molecules on Earth is around 6 miles. That’s the thickness of most of our atmosphere. Given that the Earth’s diameter is nearly 8,000 miles, 6 miles of atmosphere is only a tiny sliver. No wonder the atmosphere appears like a thin ribbon from space. For comparison, most of the atmosphere of Venus is in a layer 10 miles thick, Mars 7 miles thick.

Our atmosphere was not always rich in the oxygen needed for our survival. The air of primitive Earth, billions of years ago, consisted mainly of nitrogen, water vapor, hydrogen sulfide, methane, and carbon dioxide. These were the gases released by the molten rock of primitive Earth. And, in fact, the first life-forms on the infant Earth, such as bacteria and other microorganisms, had to live on these gases. But as plants emerged through evolutionary process, they developed the chemical machinery of photosynthesis, which absorbs carbon dioxide and releases oxygen. The era of oxygen began about 2.5 billion years ago.

For hundreds of thousands of years, human beings had no idea what our planet looked like. Could fish imagine trees on dry land? Only very, very recently in our evolutionary history have we been able to see our home planet in its fullness. And only recently have we glimpsed the thin, blue ribbon of air that keeps us alive, a fragile shield between life and death. Every inhabitant of our planet should see this photograph.

Atoms

It seems probable to me that God in the beginning formed matter in solid, massy, hard, impenetrable, moveable particles…so hard as never to wear or break in pieces.

—Isaac Newton, Optics (1704)

The idea of fundamental elements of nature can be found in all cultures and eras. Thinkers in ancient India conceived of a system of three elements for constructing the cosmos: fire, water, and earth. Fire was associated with bone and speech, water with blood and urine, earth with flesh and mind. Aristotle built the cosmos out of five elements: earth, air, water, fire, and aether (for the heavenly bodies). For the ancient Chinese, the fundamental elements were wood, fire, metal, water, and