I.
It’s difficult to find the exact
boundary between the Australopithecines, the genus of upright animals thought
to be ancestral to the genus Homo,
and the first true humans. But if we assume something like Homo habilis is the first truly distinct member of our genus, we
must try to picture the life of these earliest humans on the African savanna
some 2 million to 2.5 million years ago. How dauntingly huge the world must
have seemed to them! Probably moving in nomadic groups, the earliest of our
kind gathered food from an environment over which protracted walking was
required. Who knows the true range of their wanderings? They trudged across the
surface of their apparently huge home at ordinary walking speed, perhaps 3-4
miles per hour. (Even running as fast as they could, were they able to reach
anything like sapiens running speeds,
perhaps 27-28 miles per hour in short bursts?) Their world must have appeared
to be endless, if the exertion required to traverse its surface was any
indication. (Of course, if they possessed any concept of the totality of the world, they probably saw
the area of their own migration as its full extent.) A more advanced type of human (either a
descendant of habilis, or an entirely
independent offshoot from a common ancestor, depending on the hypothesis
accepted) known as erectus, began the
human diaspora out of Africa, perhaps as early as 1.5 million years ago. (It is
now thought that erectus did not
survive as a going concern in Asia , and that a
later African sapiens group became
the progenitors of modern humanity.) Their migration may simply have been a
matter of moving base camp a few hundred or a few thousand feet a year,
depending on the circumstances, or it may have been a migration punctuated by
long journeys stimulated by desperation or unusual conditions. (See The Diaspora of Consciousness.) But
whatever the actual timetable of a particular group’s journey, the expansion
ultimately took on a truly epic nature. Think of what physical barriers these
travelers must have encountered. We have no written record of their
experiences, but their travels must have been characterized by long periods of
dull, seemingly endless plodding punctuated by huge challenges and harrowing
dangers. And these dangers were not being met by humans of great size and
tremendous strength. The height of the average member of the genus Homo, as we will examine in greater
detail elsewhere, has averaged somewhere around five feet (about 1.5 meters),
with males generally taller than females. A small mountain of 300-400 meters in
height would be formidable to such a being; a mountain in the Alps would be
huge; and a mountain in the Himalayas would
seem unspeakably gigantic. Our ancestors roaming the eastern hemisphere
encountered such giants, and surely must have felt dwarfed by them.
In these encounters with the
world, undoubtedly many travelers lost their lives along the way. And among the
survivors, an idea was deeply impressed upon their consciousnesses: the world is enormous.
As Homo sapiens evolved, spread, and founded a wide variety of new
cultures, each group undoubtedly had its own conception of the world’s extent,
again, a conception generally limited to the area in which their tribal
hunter-gatherer group roamed. Once larger numbers of permanent settlements than
had existed in the pre-agricultural world had been founded, and literacy became
commonplace, humans (or at least that minority which was educated) began to
gain some understanding of the actual geography of the region where their group
lived. Until recent centuries, such knowledge was sketchy and speculative at
best. When humans began venturing out on epic sea journeys, from the
Phoenicians in the early 12th century BCE to the Chinese and Western Europeans
beginning in the fifteenth century CE, the sense of the Earth’s hugeness was
reinforced, as was the impression of the difficulty in crossing the Earth’s
surface. (It was not unusual, for example, for a pilgrimage from the German
states to Jerusalem
Regarding the size of the
Universe, the height of the heavens themselves, our ancestors had no real
conception. In early Mesopotamia , those who
stood at the top of ziggurats were thought to be appreciably closer to the
stars. Archimedes, perhaps the most brilliant mind of the Greco-Roman Classical
era, calculated that the Universe was, in our terms, about 12 trillion miles in
diameter—what we would call 2 light years. And with the notable exception of
Aristarchus of Samos, most educated people believed that the cosmos rotated
around us. Aristotle built his cosmology on this assumption. The great
astronomer Ptolemy deeply influenced both the Hellenistic Greek world and later
the educated Arabic-speaking world through his epic work, and both official
Christianity and Islam assumed its absolute accuracy.
But there were observations that
troubled many adherents of geocentrism. The orbits of planets, particularly
Mars, seemed “eccentric”. A weird, elaborate system of “epicycles” was invented
to try to clear up the growing numbers of observations that could not be made
to fit into an Earth-centered Universe.
Beginning with the work of Copernicus in the 16th
century CE, the picture of a geocentric cosmos began to be superseded by a new
conception of the heavens. As astronomers began to broaden the scope of their
investigations in the centuries that followed, facilitated by new and more
powerful technologies, the size of the physical Universe seemed to “grow”.
In the last century or so a revolution
has taken place in the human understanding of our planet’s physical
relationship to the Universe. Between 1917 and 1932 the most massive expansion
of our conception of the Universe’s size that has yet taken place occurred.
With the discovery during this period that the Universe was expanding, that it
contained enormous numbers of other galaxies, and was very, very old (from the
human perspective), all of our previous conceptions of the cosmic order were
systematically overthrown. And with the overthrow of our conceptions of the Universe
came another, unexpected result, one which many people have yet to confront:
the overthrow of the centrality of the human race in physical reality. This
development is momentous, perhaps as momentous as anything humans have ever
discovered about the world, and yet its full impact has yet to be felt.
II.
Our small size in relation to the Earth turned out to
be deceptive; it didn’t give us a picture of our world’s true place. In the
larger context of the physical universe, the Earth is almost unimaginably
miniscule.
We can begin by considering the Earth in relation to
objects in our own solar system. The Earth, large as it is to us, is tiny
compared to Jupiter, which has a volume more than 1,300 times that of our
planet. (The perpetual storm in Jupiter’s atmosphere, the Great Red Spot, is in
itself three times the surface area of the Earth.) The size of our neighborhood
star, the Sun, is even more overwhelming. The Sun, some 864,000 miles in diameter could hold our entire planet
over 1,300,000 times. A single arc of gas erupting from the Sun’s surface would
utterly engulf our planet were it within range of us. The diameter of the
planetary orbits in the Solar System our Sun rules over (counting the dwarf
planet Pluto) is more than 7.5 billion miles as compared to around 7,900 miles
for our little world—a ratio of more than 949,000:1. But that’s just the
start of the measure of our cosmic insignificance.
The Sun is merely a star of above average size. There are, not terribly far
from us in the Galaxy (relatively speaking), many stars of such immensity that
they dwarf our Sun. Alnilam is 27,000,000 miles in diameter, capable of holding
our Sun 30,500 times and the Earth almost 39.7 billion times. Menkar, a red giant, is 48,000,000 miles in
diameter, more than 170,000 times the volume of our Sun and 221 billion times the volume of the Earth.
Betelgeuse, a dying supergiant, is 433,000,000 miles in diameter, some 125
million times the volume of our Sun and more than 1.6 trillion times the volume of the Earth. And VY Canis Majoris, the
largest star in the Milky Way, has a diameter that on the low end is estimated at 1,600,000,000 miles, making it more than
6.3 billion times more voluminous than the Sun and 8.3 quadrillion (8.3 x 1015) times the volume of the Earth.
Astronomical distances and dimensions are so gigantic
that they are usually measured in light years (or parsecs, which are about 3.26
light years). A light year is the distance light, the fastest known thing,
travels in a vacuum in one Earth year—a distance of 5,878,499,810,000 miles.
The Milky Way Galaxy, in which our Sun is so ordinary, measures anywhere from
100,000 to 120,000 light years in diameter. Therefore, the Milky Way is (to be
on the low end of the estimate) 100,000 x 5.878499 trillion miles across—about
588 quadrillion miles. This is more than 74 trillion (7.4 x 1013)
times the diameter of the Earth. The galaxy contains anywhere from 100 billion
to 400 billion stars, depending on the number of dwarf stars that may exist.
(Incidentally, astronomers locate our solar system in a partial spiral arm of
the Milky Way Galaxy known as the Orion Spur. We are 26,000-30,000 light years
from the galaxy’s center). On such a scale, our planet’s size is already negligible. But the picture gets worse.
It was not understood until the 1920s, through the
brilliant work of Edwin Hubble, that the Milky Way Galaxy was far from being
the only one in existence. Since Hubble’s time, we have vastly improved our
observational tools, including the orbiting of space telescopes (the first one
named in Hubble’s honor, fittingly enough). And the story they tell humbles us
even more. There are whole clusters and walls of galaxies, all held together by
gravity. NASA once estimated that there were 125 billion galaxies, and
emphasized that infrared cameras, radio telescopes, and x-ray cameras might
greatly increase the estimate. Recent estimates, based on Hubble telescope
observations, run up to two trillion galaxies.
The distances between us and the closest full-fledged
galaxies are staggering. One of the nearest galaxies, the Sagittarius
Dwarf Elliptical Galaxy, is 75,000 light years away. This means a beam of light
that started traveling from our galaxy at a speed of 676,000,000 miles per hour
75,000 years ago, before any humans were in the Americas, is just arriving at
Sagittarius now. The Small Magellanic
Cloud, another “close” neighbor, is 210,000 light-years away. A beam of light
that started from our galaxy to the SMC at about the time that modern Homo sapiens were first evolving is just
arriving there now. And the nearest
spiral galaxy to us, Andromeda, is so far away that a beam of light that left
our galaxy when humans were no more than a handful of Homo habilis types living in eastern Africa
2,000,000 years ago, is just arriving there now.
Other galaxies are not just tremendously distant. Some
of the galaxies in our Universe are mind-bogglingly huge as well. In
1990, Science News announced the
following:
By carefully recording the faint light
surrounding a bright galaxy at the center of a dense cluster, a team of
astronomers has uncovered evidence for perhaps the largest and most luminous
galaxy known. This gigantic agglomeration of stars, which sits at the center of
a rich galaxy cluster called Abell 2029, extends 6 million light-years in
diameter (more than 60 times the width of the Milky Way) and emits more than a
quarter of all the light produced by the entire cluster.
Such an object has a diameter 4.7 billion times the
diameter of our Solar System’s planetary orbits. This would be as if our solar
system were eight one-hundredths of an inch across and the giant galaxy in
question were roughly the diameter of North America from the Arctic Circle to Colombia
And when the Earth is finally compared to the entire
physical Universe, the human species all but vanishes completely. The Earth’s
diameter of about 7,900 miles must be compared to the estimated 156 billion
light years diameter of the Universe. (We should recall that space can expand
faster than the speed of light.) The number of miles represented by a light
year, multiplied by 156,000,000,000 yields a staggering result: the
estimated Universe is, compared to the Earth’s diameter of 7,900 miles, more
than 116 quintillion, or to be precise, 116,071,898,734,177,215,190
(1.16071898734177215190 x 1020) times larger in diameter.
Atoms range in size from 1 x 10-10 to 5 x 10-10 of a meter in diameter. The Earth is
1.2742 x 107 meters in diameter. Therefore, the Earth is about
127.42 quadrillion times (1.2742 x 1017) the diameter of the
smallest atom. In other words, the Earth is smaller in relationship to the
Universe than the smallest atom is in relation to the Earth by a factor of
about 1,000.
III.
The creation myth believed until recently by most
humans in the Western world seemed to posit a Universe no more than a few
thousand years old. Interpreters of the Book of Genesis, for example, have
often come up with a figure of 6,000 years for the age of the cosmos, with
humans appearing within the first week of the Universe’s existence. Christian,
Jewish, and Muslim fundamentalists generally agree with this assessment.
In Tales from the Kojiki, the Japanese creation story, the age of the Universe
is said to be at least “millions and millions” of years, although the ancient
Japanese had nothing but supposition on which to rest this estimate. In Chinese
mythology, one source puts the age of the Universe at 18,000 years. Hindu
cosmologists speak in terms of enormous time periods. One Hindu belief asserts
that the Universe is more than 314 trillion years old, for example. But all of
the enormous time periods postulated in Hinduism are specifically linked to the
age of the various manifestations of God, and in all Hindu hypotheses about the
creation of the Universe, humans are present right from the start. We must assume,
additionally, that the Hindu estimates, like those of the Japanese, are based
on supposition and imagination, and not on any empirically-based observations.
All cultures have creation myths,
but they seem to share one common theme: humans are of greater or lesser
importance in them, but the act of creation by the gods or God or the infinite
has as one of its central purposes, if not the
central purpose, the creation of humans, and humans appear either immediately
at the beginning of the Universe or not terribly long after it comes into
being. All creation myths share another
commonality, as well: they have all been shredded to pieces and superseded by
the discoveries of modern science.
Recent findings from the Wilkinson Microwave Anisotropy
Probe (WMAP) space project indicate a universe 13,800,000,000 years old. The
(possibly) earliest member of the genus Homo, Homo
habilis, is thought to have emerged no earlier than 2,500,000 years ago.
Even with the discovery of a find called Toumaï' (not a member of Homo)
in Chad
Some people might prefer to think of these issues by
picturing an enormous timeline. So let’s consider this. Let’s say you have a
timeline that stretches out 1,000,000 meters in length—1000 kilometers, or about
621.3 miles. Each year since the Big Bang would be about 0.07299 millimeters on
such a scale. On this scale, we would have to travel 664,293 meters—almost
two-thirds of the total length of the line—to reach the beginning of the Earth.
We would have to travel almost 999,818 meters on that timeline to reach the
first member of the genus Homo. We
would have to travel 999,985 meters to reach the first sapiens, 999,999.2 meters to reach the earliest civilization,
and 999,999.6 meters to reach the earliest writing. The last 500 years of human
history would take up about the last 36.495 millimeters of the timeline, more
than 999,999.96 meters from the start, the lifetime of a centenarian would be
7.299 millimeters from the end of our one million meter line, and the lifespan
of a typical human in the advanced nations (about 75 years) would take us less
than 5.5 millimeters from the end of a line 1,000,000 meters in length.
We are an amazingly recent occurrence in this iteration
of the Universe. Even in comparison to the Earth, a mere 4.6 billion years in
age, we are insignificant. Imagine if the Earth were a sentient, conscious
being. Further imagine that it had the powers of observation and evaluation.
Can you imagine how fleeting the life of a seventy year old person would be to
such a being, a being almost 66,000,000 times older? It would be as if our 70
year-old simply appeared out of nowhere and then disappeared almost
instantaneously.
The rhythms of the Earth are unimaginably slow in
comparison to the frantic pace of our lives. The Earth’s memory would include
geologic eras measured in tens or hundreds of millions of years. It would
contain the earliest glimmerings of life, the upheavals and splitting apart of
whole continents, the births, lives, and deaths of countless entire species.
The recession of the last ice age, some 14,000 years ago, would be a recent
memory, comparatively speaking, to such a being. It would be the equivalent of
a memory our 70 year-old would have of something that happened 45 minutes ago!
We are newborns; we are very, very young children of
space-time and energy-matter. We were not created at the start; we were not
created near the start; we weren’t even created near the middle. We are the
latecomers. It took eons of time to produce us, and our reign on this tiny
world has been vanishingly brief. We have only just begun our journey, and
there is no guarantee that it will last much longer than it already has.
IV.
So what does this all mean? It means that all
human-centered views of the Universe are nonsense, utterly indefensible on
every level. It means that our myths were simply quaint efforts to explain
reality, based on the superstitions and limited observations of the ancient
world's people. These myths perhaps possess some literary or historical value,
but they possess no scientific value whatsoever. Our utter physical and
temporal insignificance call into question all anthropocentric views of the
Universe’s origin and various physical features. To contend that the Universe
was created for the benefit of a set of beings who occupy a world as
ludicrously small as ours, is to stretch credulity to the breaking point.
We thought we were the center of creation. We’re not.
We thought the object of the Universe’s existence was to produce us. In all
probability, it wasn’t. Perhaps, in an unspoken way, we thought if our world
disappeared it would matter to the Universe, or at least be noticed. It
probably wouldn’t.
Most humans, even though they know that the Earth is
very small and that humanity is very young, still tend to embrace some
variation of the view that everything was made for us. It is time, in my humble
opinion, for us to disabuse ourselves of this notion. The individual human life
is virtually nothing in the scale and age of the Universe in which it evolved.
This is a hard truth from which we can no longer turn, and it carries
implications that must be confronted if any kind of human dignity and worth are
to be salvaged from the wreckage of our broken dreams and shattered
mythologies.
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