April 2011 Philadelphia Chapter of Pax Christi U.S.A.

The Copernican Revolution: Shifting Paradigms

This article was reprinted in two parts in the September & December 2015 newsletters

What would common sense and sharp observation reveal about the world around us if we discarded what we have learned in school or from our society? It’s not an idle question, since we know that we see with our brains rather than our eyes. In other words, raw sense information is always filtered through a particular paradigm.

Suppose we throw away our paradigm. Let’s just use common sense and work toward a pre-scientific worldview. Let’s particularly focus on the heavens, since we need to understand celestial properties in order to navigate at sea.

We would immediately assume that we human beings are the center of everything. Hubris? Yes, but forgivable. We would see the sun and the moon rising and setting day after day, obviously revolving around the earth. The stars, on the other hand, while revolving in the same way around the earth, remain in fixed positions relative to one another. So they must be attached to a large spherical globe which rotates around us the same way that the sun and moon do. Maybe the globe is opaque with a great fire behind it; the stars then are simply holes in the stellar sphere where the light can shine through.

The stellar sphere, then, can serve as a reference against which we can judge the movement of the moon and any other freely moving objects. Observing the heavens carefully and over time, we notice that a few “stars” seem not to be attached to the stellar sphere, for they have peculiar motions of their own against the fixed stars. These we may call “planets,” meaning “wanderers.” The orbits of the sun and moon, as well as the planets, have to be perfectly circular, since the heavens are perfect and the circle is the perfect geometric shape.

Contrary to what we were taught in school, the ancients did not consider the earth to be flat. It was known, for example, that when a tall sailing ship appeared on the horizon, it was the upper mast that appeared first, while the lower part was below the horizon. Also, the shadow of the earth in a lunar eclipse was circular. Both indicate a spherical earth.

All of these beliefs and supporting assumptions we can think of as the pre-scientific paradigm. Soon it began to fall apart.

The calculations of the orbits of the planets were troublesome, requiring the assumption of “epicycles,” small circular orbits superimposed on the larger ones. Copernicus showed that the calculations could be simplified by assuming that the earth moved around the sun, although he retained the epicycles. As it happened, he saw his published book only on his deathbed. He perhaps was surprised to find that his publisher had inserted a disclaimer stating that the work simply presented a better method of calculation without claiming to represent reality. Nonetheless, the first blow had been struck against human hubris. The privileged position of humanity as the center of the universe was becoming vulnerable.

Kepler showed that the epicycles could be eliminated by assuming the planets follow elliptical rather than circular orbits. The heavens, then, were not perfect after all. The newly-invented telescope, in the hands of Galileo, showed the craters on the moon, another blow against the perfection of the heavens. His discovery of the four largest moons of Jupiter showed that Earth is not unique in having a moon. His observation of the phases of

Venus cannot be explained by any geocentric model, epicycles or not. So with Galileo the old paradigm was dead, but, of course, he had to face the Inquisition. Paradigms do not die gracefully.

Over time it became clear that the stars were individual objects, not simply holes through which light shone from the fire behind. Soon it was also seen that various stars were at different distance, some very far away indeed. So Earth became a smallish planet around a smallish sun in a larger universe. Another blow.

Among the stars there were found objects called nebulae, seeming clouds of dust without the sharp appearance of stars. Some of these were discovered to be “island universes,” galaxies, collections of billions of stars. It had been thought that our galaxy, the Milky Way, was the whole universe. Now it is revealed that our Milky Way is only one among the countless galaxies scattered across the heavens.

Well, our sun must be the center of the Milky Way, isn’t it so? No, our sun is out in one of the arms of our spiral galaxy, about 25,000 light-years from the center. Well, what’s in the center, then? A black hole. We must be unique to be clustered around a black hole, isn’t that so? No, galaxies with black holes in the center are the predominant form in the universe.

Modern observations reveal that the universe is expanding, actually at an accelerating rate, so that all galaxies are moving away from us. (The stars within a galaxy are not moving away from one another, since they are bound by gravity.) So our galaxy must be at the center of the universe. No, everything is expanding from the geometric point at the creation moment, so that observers from anywhere in the universe would see all galaxies moving away from them. Our galaxy is not special.

It must be that Earth was created in the very beginning and the rest created around it. No, the initial creation moment was 13.7 billion years ago, and our sun was born only about five billion years ago, and Earth shortly thereafter. It was necessary to have a supernova explosion before that so that the higher elements needed for life could be made available. So the birth of Earth was almost an afterthought from the violent self-sacrifice of a giant parent star. Humility upon humility.

The currently accepted theory about the origin and nature of the universe, the “hot big bang” theory, includes a period of “inflation” during the first small fraction of a second, when the young universe expanded at a rate many times the rate before or after. The theory suggests that during the inflationary period multiple universe could have been the created, some with characteristics radically different from our own. Most of them would probably be unsuitable for the development of life. So maybe our universe is just one attempt, fortunately for us successful, among many unsuccessful universes. So maybe we are one universe among many.

Finally, we are intelligent beings, and that must be unique. No, most cosmologists are in agreement that in the billions of galaxies, there must be many planets like ours which nurture intelligent life, some of which may be far advanced and superior to ourselves.

Are we insignificant, then? Not at all. We just have to put aside our species arrogance and recognize our humble place in the web of life on our humble planet, in our humble galaxy, perhaps in our humble universe. Out of that humility there can arise great power, for we have our spiritual side. Each of us is unique and capable of spreading peace and compassion by being our authentic selves. We don’t need to be special.

Dom Roberti, PhD Dom, a very generous active member of CPF, died on July 15, 2014