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☞ Pensieri a caso
☞ A Box Of Stories
Lucretius on the infinite universe, the beginning of things and the likelihood of extraterrestrial life
All things [the particles]
move everywhere, always in constant motion—
material stuff is stirred up and supplied
from down below out of infinite space.
This, therefore, is the nature of deep space
and its extent—bright lightning in its course
could not pass through it—though sliding forward
for unending tracts of time, its motion,
as it proceeded, would not diminish
the remaining distance it still had to go.
That shows how much immense space lies open
on all sides for things, free from all limits
everywhere in all directions.
nature herself makes sure the universe
cannot set limits to itself—she compels
matter to be enclosed within a void,
and void, in turn, to be bound by matter.
With this reciprocal relationship
she therefore makes the total infinite,
or else one of the two, if the other
did not limit it, in its unmixed form
would then extend out beyond all measure.
[But I have shown above that space spreads out
without limit; thus, matter, too, must be
infinite, for if the void were endless,
and the total sum of matter finite,]
neither sea nor earth nor sky’s bright spaces,
nor mortal races, nor sacred bodies
of the gods could endure for very long,
not even for the short space of an hour,
since, with their combined masses forced apart,
supplies of matter would be carried off
and scattered through huge areas of space,
or what is, in fact, more likely, matter
would never have united and therefore
would never have produced a single thing,
since, in its dispersed condition, it would
be incapable of forming compounds.
For clearly the first particles of things
did not all place themselves in due order
by their own planning or intelligence,
nor did they through some agreement assign
the motions each of them should have. Instead,
since there are many of them and they change
in many ways through all the universe,
they are pushed, energized by collisions,
for a limitless length of time, and then,
having gone through every kind of motion
and combination, they at length fall into
those arrangements which make up and create
this totality of things, which also,
once suitably set in patterned motion,
has been preserved through many lengthy years.
It makes rivers with large flows of water
refresh voracious seas, and earth, once warmed
by sun’s heat, restore what it produces,
races of living creatures grow and thrive,
and, in the aether, gliding fires live on.
There would be no way they could act like this,
unless supplies of matter kept arising
from infinite space, stuff which they then use
to restore, over time, what has been lost.
Thus, to repeat myself, many particles
must spring up. And yet to be capable
of keeping the number of those impacts
at a sufficient level, there must be
infinite amounts of matter on all sides.
In these things, Memmius, stay far away
from having faith what some people say—
that all matter presses to the centre
of the universe and for this reason
the substance of the world remains in place
without any collisions from outside,
and that the bottom and the top cannot
be forced apart in any direction,
since all matter sinks towards the centre—
if you believe that anything can stand
upon itself—and that all heavy things
on the lower part of earth press upward
and remain there, placed upside down on earth,
just as we now see images of things
— I [996-1061] p.45-47.
To start with, we know that in every part,
in all directions and on either side,
above and below and throughout all space,
there is no limit, as I have explained,
and facts themselves announce it on their own—
the nature of deep space is very clear.
Since infinite space lies empty on all sides
and seeds in countless numbers fly around
through the deep universe in various ways,
driven by eternal motion, we must not,
in any way, now think it probable
that only this one sphere of earth and sky
have been created, that beyond us here
all those many particles of matter
do nothing at all, especially since earth
was made by nature. Seeds of things themselves,
jostling freely here and there in various ways
and forced to random, confused collisions,
produced nothing—then finally those ones
suddenly united which could become,
every time, the beginnings of great things,
land, sea, sky, the race of living beings.
And so, to repeat myself, you must grant
that there are other aggregates of matter
similar to this in other places,
which aether clutches in its keen embrace.
Further, when large quantities of matter
are on hand and there is sufficient space,
with no causal factor standing in the way,
we may be sure that things must be produced
and their full development completed.
Now, if supplies of seed are so enormous
that all the years of living animals
could not count the total, and if nature
and the same force remain which could collect
the seeds of matter into every place
in the same way they are thrown together here,
one must grant there are other earthly spheres
in other regions, with different races
of human beings and classes of wild beasts.
Add to this that in the whole universe
no single thing exists all on its own:
nothing is born unique and flourishes
as the single specimen of its kind.
Instead it always belongs to some race,
and those of the same kind are numerous.
If, to begin with, you direct your mind
to living creatures, you will discover
this is true for living varieties
of savage animals which roam the hills,
true for human offspring, and it is true
for mute herds of scaly fish and all bodies
of things which fly. Thus, one must acknowledge,
that, in the same way, sky, land, sun, moon, sea,
and all the other objects which exist
are not unique—instead their quantity
is beyond all counting.
If you grasp these points well and hold to them,
you will see at once that nature is free,
liberated from her proud possessors,
doing all things on her own initiative,
without divinities playing any part.
— II [1047-1094] p. 89-90.
Since the moment earth was first created,
that day sea, land, and rising sun were born,
many particles have been added on
from areas outside. All around them,
seeds which the immense universe has joined
by hurling them about have been attached.
Because of that, sea and lands could increase,
the mansion of the sky could gain more space
and raise its high roof far above the land,
and air could flow there.
— II [1103-1112] p. 91.
☞ How Epicurus’ ideas survived through Lucretius’ poetry, and led to toleration, Lapidarium notes
☞ Lucretius: ‘O unhappy race of men, when they ascribed actions to the gods’
☞ Definitions: Atom, Matter, Universe, Higgs boson, Wiki
Obviously it doesn’t matter that much if you’re a beetle, that you be really smart. If it were, evolution would have produced much more intelligent beetles. We have no empirical data to suggest that there’s a high probability that evolution on another planet would lead to technological intelligence.
Sir Martin Rees on our understanding of the universe
“I would say that although the earth is very small, it is one of the most important places in the galaxy. It is the one place where we know that something very complicated has evolved. That process has led from simple life by Darwinian evolution to creatures like ourselves, able to understand our origins and contemplate the wonder and the mysteries of the universe. We should not be impressed by sheer size but should also admire the intricate complexity of all the things on the earth. And the most complicated things that we know about are human beings. (…)
Q: You have said that there might have been more than just one Big Bang. How could that be?
Sir Rees: Of course it is just a speculation. But it is certainly possible, indeed likely, that there was a lot more to physical reality than the volume which we can probe with our telescopes. And almost everyone will agree that there many galaxies which are beyond the limits of what we can see with our telescopes. A few hundred years ago, nobody would have believed that our sun is not unique or that our galaxy is not the only galaxy. Thinking about the properties of the Big Bang is thus an entirely legitimate speculation. (…)
I don’t see it as an humiliation. We should not be impressed by size. What is important is complexity. Even an insect can be more impressive than a star because it is more complex. New discoveries about the universe should not take away the realization of our own complexity. (…)
Q: Is religion still a concept helping us to understand the hugeness and the variety that surrounds us? (…)
I think the universe revealed by modern science is a more wonderful place to live in than the rather more limited and constricted view that people had of the universe in the past. (…)” “
Our attempts to understand the universe are akin to standing on a beach for a few hours peering through a drinking straw and from that information drawing conclusions about the nature and history of life on Earth.
“The evolution o life-forms on Earth seems to move in the direction of organisms that are increasingly cognizant of the subdimensions of space and time. A short excursion through the phyla will establish the hierarchy of this imperative. Plants, the planet’s earliest biological adventure, cannot perceive any dimensions because they do not have nervous systems. It must be a given that the appreciation of space and time requires some kind of apparatus with which to do so. Plants represent the “point” of Euclidean geometry. The first animal organisms, denied the use of the sun as a primary energy source, ate the plants as a substitute. But to consume the algae, the single-cell herbivores had to find them. A paramecium or amoeba, propelling itself toward nutritional stimulae and recoiling from noxious ones, lives out its life in a one-dimensional tunnel. Its sentience is so rudimentary that one can say it exists only in the first dimension of space: a “line”.
Not until the advent of flatworms does a nervous system appear that is elongated into a neural tube with a protuberance at the front end that branches into two lateral lobes. It is probably here that an organism begins to appreciate space from side to side, as well as to and fro. Because it has developed right and left symmetry, the elemental worm-brain is the likely candidate first to have apprehended the second spatial dimension, breadth. Existence for this organism is played out upon a geometrical “plane.” Planaria, the flatworm, is the original “Flatlander.”
When Devonian fish evolved with an eye and a cerebellum, they achieved the capacity for a full appreciation of the third spatial dimension, depth. From the vertebrates onward, all life-forms had the neurological equipment necessary to apprehend all three vectors of Euclidean space: length, breadth, and depth. Their world was contained within Euclid’s solid geometrical shape: a cube.
Still missing from our story of evolution is a sense of time. None of the aforementioned organisms experiences duration. They need no awareness of time because their internal clocks are set by genetics and instinct alone. Programmed into their behavior pattern are the earth’s daily revolution, the lunar periodicity, and the yearly equinoxes. Instead of a sense of time, they have what biologists call circadian rhythms. All organisms up to and including reptiles live in the thin slice of the present. to a fish, to a flatworm, to an amoeba, there is no past, and there is no future. Since it lacks the power of recollection, it is not possible for a crocodile to remember who or what it ate for lunch. All animals up the evolutionary chain through reptiles are prisoners locked in the solitary confinement of the flickering now.” “
Leonard Shlain, Art & Physics: Parallel Visions in Space, Time, and Light, New York: Harper Perennial, 1991. 2007 (tnx carvalhais)
“I mention all this to make the point that if you were designing an organism to look after life in our lonely cosmos, to monitor where it is going and keep a record of where it has been, you wouldn’t choose human beings for the job.
But here’s an extremely salient point: we have been chosen, by fate or Providence or whatever you wish to call it. It’s an unnerving thought that we may be living the universe’s supreme achievement and its worst nightmare simultaneously. Because we are so remarkably careless about looking after things, both when alive and when not, we have no idea — really none at all — about how many things have died off permanently, or may soon, or may never, and what role we have played in any part of the process.
In 1979, in the book The Sinking Ark, the author Norman Myers suggested that human activities were causing about two extinctions a week on the planet. By the early 1990s he had raised the figure to about some six hundred per week. (That’s extinctions of all types— plants, insects, and so on as well as animals.) Others have put the figure ever higher — to well over a thousand a week. A United Nations report of 1995, on the other hand, put the total number of known extinctions in the last four hundred years at slightly under 500 for animals and slightly over 650 for plants— while allowing that this was “almost certainly an underestimate,” particularly with regard to tropical species.
A few interpreters think most extinction figures are grossly inflated.
The fact is, we don’t know. Don’t have any idea. We don’t know when we started doing many of the things we’ve done. We don’t know what we are doing right now or how our present actions will affect the future. What we do know is that there is only one planet to do it on, and only one species of being capable of making a considered difference. Edward O. Wilson expressed it with unimprovable brevity in The Diversity of Life: “One planet, one experiment.”
If this book has a lesson, it is that we are awfully lucky to be here— and by "we" i mean every living thing. To attain any kind of life in this universe of ours appears to be quite an achievement. As humans we are doubly lucky, of course: We enjoy not only the privilege of existence but also the singular ability to appreciate it and even, in a multitude of ways, to make it better. It is a talent we have only barely begun to grasp.
We have arrived at this position of eminence in a stunningly short time. Behaviorally modern human beings— that is, people who can speak and make art and organize complex activities— have existed for only about 0.0001 percent of Earth’s history. But surviving for even that little while has required a nearly endless string of good fortune.
We really are at the beginning of it all. The trick, of course, is to make sure we never find the end. And that, almost certainly, will require a good deal more than lucky breaks.” “
“If you imagine the 4,500-bilion-odd years of Earth's history compressed into a normal earthly day, then life begins very early, about 4 A.M., with the rise of the first simple, single-celled organisms, but then advances no further for the next sixteen hours. Not until almost 8:30 in the evening, with the day five-sixths over, has Earth anything to show the universe but a restless skin of microbes.
Then, finally, the first sea plants appear, followed twenty minutes later by the first jellyfish and the enigmatic Ediacaran fauna first seen by Reginald Sprigg in Australia. At 9:04 P.M. trilobites swim onto the scene, followed more or less immediately by the shapely creatures of the Burgess Shale. Just before 10 P.M. plants begin to pop up on the land. Soon after, with less than two hours left in the day, the first land creatures follow.
Thanks to ten minutes or so of balmy weather, by 10:24 the Earth is covered in the great carboniferous forests whose residues give us all our coal, and the first winged insects are evident. Dinosaurs plod onto the scene just before 11 P.M. and hold sway for about three-quarters of an hour. At twenty-one minutes to midnight they vanish and the age of mammals begins. Humans emerge one minute and seventeen seconds before midnight.
The whole of our recorded history, on this scale, would be no more than a few seconds, a single human lifetime barely an instant. Throughout this greatly speeded-up day continents slide about and bang together at a clip that seems positively reckless. Mountains rise and melt away, ocean basins come and go, ice sheets advance and withdraw. And throughout the whole, about three times every minute, somewhere on the planet there is a flash-bulb pop of light marking the impact of a Manson-sized meteor or one even larger. It’s a wonder that anything at all can survive in such a pummeled and unsettled environment. In fact, not many things do for long.” “
“If you expected science to give all the answers to the wonderful questions about what we are, where we are going what the meaning of the universe is and so on then I think you can easily become disillusioned and then look for some mystic answer to these problems. How a scientist can take a mystic answer I don’t know because the whole spirit is to unders…well never mind that, anyway I don’t understand that…but anyhow…if you think of it though…I..the way i think of what we are doing is, we are exploring, we are trying to find out as much as we can about the world.
People say to me, “Are you looking for the ultimate laws of physics?” No I am not. I am just looking to find out more about the world. And if it turns out there is a simple ultimate law that explains everything so be it. That would be very nice discovery. If it turns out it’s like an onion with millions of layers and we just sick and tired of looking at the layers then that’s the way it is! But whatever way it comes out it’s nature, it’s there, and she’s going to come out the way she is. And therefore when we go to investigate we shouldn’t pre-decide what it is we are trying to do except to find out more about it. If you said…but..the problem is why we do you find out more about it, if you thought that you are trying to find out more about it because you are going to get an answer to some deep philosophical question you may be wrong and may be that you can’t get an answer to that particular question by finding out more about the character of the nature.
But I don’t look it at…my interest in science is to simply find out about the world…and the more I find out and…I like to find out…and there are very remarkable mysteries about the fact that we are able to do so many more things and apparently animals can do.
And other questions like that. Those are the mysteries I want to investigate without knowing the answer to them. So …altogether I can’t believe the special stories that’ve been made up about our relationship to the universe at large because they seem to be…too simple, too connected, too local, too provincial. The “earth,” He came to “the earth”, one of the aspects God came to “the earth!” mind you, and look at what’s out there…? how can we…? it isn’t in proportion…!
Anyway it’s no use to argue, I can’t argue. I am just trying to tell you why the scientific views that I have do have some affect on my beliefs. And also another thing has to do with the question of how do you find out if something is true? And if you have all these theories of the different religions and all different theories about the thing then you begin to wonder…once you start doubting… just like you are supposed to doubt, you asked me if science is true, no no we don’t know what is true…no no we don’t know, we are trying ……start out understanding religion by saying everything is possibly wrong, let us see, as soon as you do that you start sliding down an edge which is harder to recover from. And one…so with the scientific view or my father’s view that we should look to see what’s true and what may not be true, once you start doubting ……which I think, to me, is a very fundamental part of my soul is to doubt and to ask, when you doubt and ask it gets a little harder to believe.
You see, one thing, is I can live with doubt and uncertainty and not knowing. I think it’s much more interesting to live not knowing than to have answers which might be wrong. I have approximate answers and possible beliefs and different degrees of certainty about different things but I’m not absolutely sure of anything and then many things I don’t know anything about, such as whether it means anything to ask, “Why we are here?” and what that question might mean. I might think about it a bit and then if I can’t figure it out then I go on to something else.
But I don’t have to know an answer, I don’t have to…i don’t feel frightened by not knowing things, by being lost in the mysterious universe without having any purpose which is the way it really is as far as I can tell possibly. It doesn’t frighten me.” “