Whether or not we are alone in the universe is one of the great questions that has haunted humanity since its early days. Long before we developed an elaborate scientific understanding of the cosmos, the inhabitants of the ancient world looked up at the sky and populated it with mythical creatures and gods. But although the ancient peoples throughout the Near and Far East, and North Africa created elaborate hypotheses and lore about the origin of humanity, the world and its place in a greater scheme of things, the 6th-century B.C.E. Greek philosopher Anaximander of Miletus may have been the first to develop a systematic philosophical view of the world.
He was the first we know of to realize that the Earth is a body drifting in an infinite void, supported by nothing. That was an extraordinarily advanced statement for his time, and was not diminished by his belief that Earth was cylinder-shaped (you can’t always be right).
Anaximander also held that everything was born from the apeiron, which translates to “boundless” or “infinite”, rather than from a singular component, such as water, as the philosopher Thales of Miletus had previously suggested. He believed that everything was comprised of that primordial substance, from animals, to trees, to people, and the celestial bodies. Everything around us, including ourselves, is cosmic. The thinker envisioned a perpetual flow of matter, a continuous expansion, that could be interpreted as a constant becoming of things.
He was also an early subscriber to the belief that the world is not eternal; it has an expiry date and will eventually be swallowed back into the apeiron, from which new worlds will form. Anaximander was therefore the first to say that the existence of our world is not a unique wonder in the universe.
According to the philosopher, all creations must “pay penalty and retribution to one another for their injustice, according to the disposition of time,” as he metaphorically expressed.
Some five centuries later, the Stoic emperor Marcus Aurelius reflected on the cosmos as one living organism in his set of essays called “Meditations”: “Constantly think of the universe as a single living being, comprised of a single substance and a single soul; and how all things issue into the single perception of this being, and how it accomplishes all things through a single impulse; and how all things work together to cause all that comes to be, and how intricate and densely woven is the fabric formed by their interweaving.”
What the eyes can’t see
Anaximander’s successors went on to further explore the thrilling idea of a plurality of worlds. The 5th-century B.C.E. Greek philosopher Leucippus made a daring assertion. He developed the theory of atomism further with his famous student, Democritus, who was dubbed the “laughing philosopher” because he held that cheerfulness was an objective to pursue in life. The two envisioned the universe consisting of homogeneous matter, made of an infinity of small indivisible particles called atoms.
These atoms are constantly in motion without purpose or cause, and through their collisions and regroupings, form various compounds. They came to the conclusion that Earth is not a divine creation but a result of atoms colliding and sticking together- a purely mechanical picture of the universe.
Since there was an infinite pool of atoms, the two philosophers argued, there must be potentially an endless number of worlds. Maybe that conclusion was the very reason behind Democritus’ state of constant gaiety. After all, if the whole world is in denial, why not laugh at it?
Either way, Democritus’s insights inspired other thinkers. As his pupil, Metrodorus of Chios stated: “It seems absurd that in a large field only one stalk should grow, and in an infinite space only one world exists.”
It is worth noting that there is no real difference between his assertion and modern arguments for extraterrestrial intelligence based on the so-called “principle of Copernican mediocrity” (named after the Polish astronomer Nicolaus Copernicus). The principle states that our planet does not occupy a privileged spot in the universe and, consequently, the processes on Earth that led to life development, and ultimately to thinking beings, may have also occurred throughout the cosmos.
The other worlds
The Greek thinker Epicurus famously founded Epicureanism, a philosophy focusing on pleasure as the greatest good, which is best secured through modest, self-sufficient living. But he was also able to think beyond human existence.
In a letter to his acclaimed friend Herodotus, he wrote, “There are an infinite number of worlds, some like this world, others unlike it. For the atoms being infinite in number, as has just been proved, are borne ever further in their course. For the atoms out of which a world might arise, or by which a world might be formed, have not all been expended on one world or a finite number of worlds, whether like or unlike this one. Hence, there will be nothing to hinder an infinity of worlds. “What is fascinating about the letter is that the philosopher considers not only an unlimited number of worlds but also worlds entirely different from ours, which was quite audacious for the time.
Intriguingly, both Plato and Aristotle, considered the most influential intellectual figures of classical antiquity, rebuked the idea of a plurality of worlds. Plato, who was a monotheist, asserted that since there is only one creator, there can be only one world, “if the created copy is to accord with the original,” of course. According to the philosopher, those who tried to argue with reason were sad, indecisive creatures with ignorant minds. “I know that I know nothing” is a phrase from Plato’s teacher, Socrates. Perhaps the philosopher should have held to it a bit longer.
Aristotle also thought the hypothesis outlandish. He argued that a plurality of worlds would need a plurality of prime movers to keep them in motion — a self-contradictory idea. The theory of infinite worlds clashed with his view of physics.
Yet the notion of alien worlds, however faint and mocked, made it from Mesopotamia and ancient Greece to ancient Rome. The 1st century B.C.E. Roman poet Lucretius, known for his single, long poem, ‘On the Nature of Things’, gives a brief but profound view of the existence of alien worlds:
“If store of seeds there is
So great that not whole life-times of the living
Can count the tale …
And if their force and nature abide the same,
Able to throw the seeds of things together
Into their places, even as here are thrown
The seeds together in this world of ours,
‘Tmust be confessed in other realms there are
Still other worlds, still other breeds of men,
And other generations of the wild.”
In his poem, the universe is populated with other cosmic worlds, in which extraterrestrial intelligence exists. What is also remarkable about the passage is that Lucretius refers to “other breeds of men”, implying that humans might be just one of countless intelligent races in the universe. After all, there is enough room to share.
Ancient UFOs
But what would be the extraterrestrial discussion without UFOs? Turns out that already in ancient times, people were witnessing shining objects in the sky and drawing extreme conclusions.
For instance, the Roman historian Livy writes that during the winter of 218 B.C.E., there was a “spectacle of ships gleaming in the sky”. Livy reports another arrival in the sky in 173 B.C.E., when a “great fleet” materialized over a city named Lanuvium (today the city of Lanuvio, southeast of Rome). Earlier, in the spring of 217 B.C.E., as the Carthaginians led by Hannibal threatened Rome, Livy states that “round shields were seen in the sky” over central Italy.
He was not the only historian reporting on mysterious objects in the sky. Plutarch reports that when Lucullus’ forces were about to fight King Mithridates VI of Pontus in the first century B.C.E., a strange object appeared between the two armies: “Suddenly, the sky burst asunder, and a huge, flame-like body was seen to fall between the two armies. In shape, it was most like a wine-jar (pithos), and in color, like molten silver. Both sides were astonished at the sight and separated.”
The Roman author Pliny the Elder also reports a dazzling phenomenon that took place in 76 B.C.E., at about the same time as the fight against Pontus, that would have been truly worthy of a Hollywood production: “We have an account of a spark falling from a star, and increasing as it approached the earth, until it became of the size of the moon, shining as through a cloud; it afterwards returned into the heavens and was converted into a lampas; this occurred in the consulship of Cn. Octavius and C. Scribonius. It was seen by Silanus, the proconsul, and his attendants.”
The cosmic Dark Ages
But as Christianity took over the dying Roman Empire, the clergy further ridiculed and suppressed atomism, together with the theory of cosmic pluralism. The 6th century Christian bishop St Augustine pointed out that if there are other intelligent beings somewhere in the universe, they would also need a Savior, which would diminish the act of the crucifixion – a bitter pill to swallow.
Another problem arose because that Christianity was profoundly anthropocentric. The universe was created for Man, a theological argument that did not fit well in a plurality of worlds.
However, the discussion was not completely over. In the 13th century, the German theologian St. Albertus Magnus pondered, “Do many worlds exist, or is there but a single world?”
The conviction in the principle of plentitude made him not reject the idea of plurality. If God is almighty, why would he bother to create just one world instead of all possible worlds reflecting his infinite might, he wondered.
Ultimately, Albertus Magnus succumbed to the plain reasoning and rejected the possibility of cosmic pluralism, founding his argument on Christ’s sacrifice and the good old Aristotelian physics.
St. Thomas Aquinas, who seemed bored with his colleagues’ reflections, found a solution to the complex matter – he rejected the plurality of worlds, the infinite universe and the principle of plenitude altogether: “The very order of things created by God shows the unity of the world. … Therefore it must be that all things should belong to one world.”
Of course, not everyone was impressed. St. Bonaventure, the Italian Franciscan theologian who joined God’s realm the same year as Aquinas, was clearly not convinced by his Dominican colleague’s drastic measures. He stated that if God wished, He could simply suspend Aristotelian physics and make as many worlds as He liked.
Of course, there were a few more who tried to resolve the ancient dispute, including the 16th-century Italian philosopher Giordano Bruno, who was inspired by Nicolaus Copernicus’s writing ‘On the Revolution of the Celestial Spheres’. He decided that there might be other planets inhabited by intelligent life similar to that on Earth. Refusing to come to his senses and “sober up”, he was burned at the stake after seven years of imprisonment and torture.
Following that, the majority of the following theologians felt uncomfortable with the idea of extraterrestrial worlds. Christianity would only begin to come to terms with the possibility of alien life in the 20th century, moving the debate from whether there are aliens (still an open debate) to whether they would need salvation.
The field of exotheology is still in its infancy, as is, frankly, the search for extraterrestrial life. The chances are and remain – we will never know, which may be for the best.
As the renowned British astrophysicist Stephen Hawking warned, we should stay silent and stop actively attempting to communicate with extraterrestrial civilizations. “We only have to look at ourselves to see how intelligent life might develop into something we wouldn’t want to meet,” Hawking said. “I imagine they might exist in massive ships … having used up all the resources from their home planet. Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they can reach.” We might be merely little fishes in a vast ocean full of sharks.
