What I know about worldviews in cosmology comes from researching the extraterrestrial life debate, the term used by historians of science to describe the ideas of philosophers, literary figures, theologians, astronomers, and other scientists about the presence or absence of (usually) intelligent life elsewhere in the cosmos. This isn't a conventional route to or through cosmology, but it works for me.
Which is not to say that what I know about cosmological worldviews is anything special. But I do know this: there are clear and interesting connections between developments in astronomy -- its history as an evolving body of knowledge and its literal reach into space/time through advances in technology -- and how astronomers and the rest of us tend to "see" the Universe. In other words, how we in West, anyway, broadly think about the stars we see, and don't see, and what the culture around us, including astronomy, has to do with these thoughts.
This is the general theme of next month's Astronomy and Civilization conference in Budapest, which I wrote about last time and, of course, it's also a general theme of Cosmology Bus.
Recently I re-read the last chapter of Steven Dick's The Biological Universe: The Twentieth-Century Extraterrestrial Life Debate and the Limits of Science (see Books sidebar), which I knew contained a discussion of cosmology in light of the debate. In it, he describes the biological universe -- an evolving cosmos containing many planetary systems where conditions capable of supporting life will produce life, some of which could evolve intelligence under the right conditions -- as a legitimate worldview. For Dick, this perspective combines "the biophysical universe with the characteristics physical universe," which he calls "biophysical cosmology."
Dick also mentions several astronomers who anticipated this development. Among them was Harlow Shapley (1885-1972), a very interesting guy who in his early 30s discovered something that changed the way people think about the night sky we see: that the Milky Way Galaxy was much larger than was previously thought, and that our sun was not at its center.
Shapley found that the star we orbit, and by extension our solar system, lies at the galaxy's edge in a minor spiral arm we now call the Orion Spur, or sometimes the Local Spur.
Talk about deflating.
And in part, that's the point: throughout human history, major shifts in what we understand about our place in the universe have redefined our perspectives or worldviews, and in this process the new knowledge has usually punctured our collective ego.
Shapley wrote about this nearly sixty years ago in a very readable article published in The American Scholar called "Man's Fourth Adjustment." In the piece he identifies four shifts involving our relationship to the physical universe:
- Anthropocentric to Geocentric [Man is the focus or center of the universe to Earth is the center]
- Geocentric to Heliocentric [Earth is the center to our Sun is the center]
- Heliocenric to Galactocentric [Our Sun is the center to the idea that the universe is an immense collection of galaxies containing countless planetary systems]
- We Are Not Alone [Life is widely distributed in galaxies across the universe]
Shapley has this just about right, I think, even while acknowledging the then (and current) absence of evidence demonstrating that life exists beyond Earth. I also appreciate his comments on the impact of a galactocentric worldview:
"The 'galactocentric universe' suddenly puts the earth and its life near the edge of one great galazy in a universe of galaxies. Man becomes peripheral among the billions of stars of his own Milky Way; and, according to the revelations of paleontology and geochemistry, he is recent and apparently ephemeral in the unrolling of cosmic time. And here is a somber or happy thought, whichever mood you prefer. There is no retreat! The inquiring human has passed the point of no return. We cannot restore geocentrism or heliocentrism . . . . And since we cannot go back to the cramped but comfortable past (without sacraficing completely our cultures and civilizations), we go forward and find there is more to the story."
I like his take on the "cramped but comfortable past" and the no-retreat reality of our unfolding story. The concluding sentence of the article also speaks directly to one of my own long-standing interests in the topic:
"In conclusion, I need not emphasize the possible relevance to philosophy and to perhaps religion to this fourth adjustment in man's view of himself in the material universe."
Looking at the extraterrestrial life debate, a worldview encompassing the idea that we are not alone can't help but touch religion, and especially the monotheistic world religions.
How religions respond to this adjustment will say much about their future.
Next stop: tbd
Banner bus photo credit: Dorothy Delina Porter