Now come: I will untangle for thy steps
Now by what motions the begetting bodies
Of the world-stuff beget the varied world,
And then forever resolve it when begot,
And by what force they are constrained to this,
And what the speed appointed unto them
Wherewith to travel down the vast inane:
Do thou remember to yield thee to my words.
For truly matter coheres not, crowds not tight,
Since we behold each thing to wane away,
And we observe how all flows on and off,
As 'twere, with age-old time, and from our eyes
How eld withdraws each object at the end,
Albeit the sum is seen to bide the same,
Unharmed, because these motes that leave each thing
Diminish what they part from, but endow
With increase those to which in turn they come,
Constraining these to wither in old age,
And those to flower at the prime (and yet
Biding not long among them). Thus the sum
Forever is replenished, and we live
As mortals by eternal give and take.
The nations wax, the nations wane away;
In a brief space the generations pass,
And like to runners hand the lamp of life
One unto other.
But if thou believe
That the primordial germs of things can stop,
And in their stopping give new motions birth,
Afar thou wanderest from the road of truth.
For since they wander through the void inane,
All the primordial germs of things must needs
Be borne along, either by weight their own,
Or haply by another's blow without.
For, when, in their incessancy so oft
They meet and clash, it comes to pass amain
They leap asunder, face to face: not strange-
Being most hard, and solid in their weights,
And naught opposing motion, from behind.
And that more clearly thou perceive how all
These mites of matter are darted round about,
Recall to mind how nowhere in the sum
Of All exists a bottom,- nowhere is
A realm of rest for primal bodies; since
(As amply shown and proved by reason sure)
Space has no bound nor measure, and extends
Unmetered forth in all directions round.
Since this stands certain, thus 'tis out of doubt
No rest is rendered to the primal bodies
Along the unfathomable inane; but rather,
Inveterately plied by motions mixed,
Some, at their jamming, bound aback and leave
Huge gaps between, and some from off the blow
Are hurried about with spaces small between.
And all which, brought together with slight gaps,
In more condensed union bound aback,
Linked by their own all intertangled shapes,-
These form the irrefragable roots of rocks
And the brute bulks of iron, and what else
Is of their kind...
The rest leap far asunder, far recoil,
Leaving huge gaps between: and these supply
For us thin air and splendour-lights of the sun.
And many besides wander the mighty void-
Cast back from unions of existing things,
Nowhere accepted in the universe,
And nowise linked in motions to the rest.
And of this fact (as I record it here)
An image, a type goes on before our eyes
Present each moment; for behold whenever
The sun's light and the rays, let in, pour down
Across dark halls of houses: thou wilt see
The many mites in many a manner mixed
Amid a void in the very light of the rays,
And battling on, as in eternal strife,
And in battalions contending without halt,
In meetings, partings, harried up and down.
From this thou mayest conjecture of what sort
The ceaseless tossing of primordial seeds
Amid the mightier void- at least so far
As small affair can for a vaster serve,
And by example put thee on the spoor
Of knowledge. For this reason too 'tis fit
Thou turn thy mind the more unto these bodies
Which here are witnessed tumbling in the light:
Namely, because such tumblings are a sign
That motions also of the primal stuff
Secret and viewless lurk beneath, behind.
For thou wilt mark here many a speck, impelled
By viewless blows, to change its little course,
And beaten backwards to return again,
Hither and thither in all directions round.
Lo, all their shifting movement is of old,
From the primeval atoms; for the same
Primordial seeds of things first move of self,
And then those bodies built of unions small
And nearest, as it were, unto the powers
Of the primeval atoms, are stirred up
By impulse of those atoms' unseen blows,
And these thereafter goad the next in size;
Thus motion ascends from the primevals on,
And stage by stage emerges to our sense,
Until those objects also move which we
Can mark in sunbeams, though it not appears
What blows do urge them.
Herein wonder not
How 'tis that, while the seeds of things are all
Moving forever, the sum yet seems to stand
Supremely still, except in cases where
A thing shows motion of its frame as whole.
For far beneath the ken of senses lies
The nature of those ultimates of the world;
And so, since those themselves thou canst not see,
Their motion also must they veil from men-
For mark, indeed, how things we can see, oft
Yet hide their motions, when afar from us
Along the distant landscape. Often thus,
Upon a hillside will the woolly flocks
Be cropping their goodly food and creeping about
Whither the summons of the grass, begemmed
With the fresh dew, is calling, and the lambs
Well filled, are frisking, locking horns in sport:
Yet all for us seem blurred and blent afar-
A glint of white at rest on a green hill.
Again, when mighty legions, marching round,
Fill all the quarters of the plains below,
Rousing a mimic warfare, there the sheen
Shoots up the sky, and all the fields about
Glitter with brass, and from beneath, a sound
Goes forth from feet of stalwart soldiery,
And mountain walls, smote by the shouting, send
The voices onward to the stars of heaven,
And hither and thither darts the cavalry,
And of a sudden down the midmost fields
Charges with onset stout enough to rock
The solid earth: and yet some post there is
Up the high mountains, viewed from which they seem
To stand- a gleam at rest along the plains.

Now what the speed to matter's atoms given
Thou mayest in few, my Memmius, learn from this:
When first the dawn is sprinkling with new light
The lands, and all the breed of birds abroad
Flit round the trackless forests, with liquid notes
Filling the regions along the mellow air,
We see 'tis forthwith manifest to man
How suddenly the risen sun is wont
At such an hour to overspread and clothe
The whole with its own splendour; but the sun's
Warm exhalations and this serene light
Travel not down an empty void; and thus
They are compelled more slowly to advance,
Whilst, as it were, they cleave the waves of air;
Nor one by one travel these particles
Of the warm exhalations, but are all
Entangled and enmassed, whereby at once
Each is restrained by each, and from without
Checked, till compelled more slowly to advance.
But the primordial atoms with their old
Simple solidity, when forth they travel
Along the empty void, all undelayed
By aught outside them there, and they, each one
Being one unit from nature of its parts,
Are borne to that one place on which they strive
Still to lay hold, must then, beyond a doubt,
Outstrip in speed, and be more swiftly borne
Than light of sun, and over regions rush,
Of space much vaster, in the self-same time
The sun's effulgence widens round the sky.

Nor to pursue the atoms one by one,
To see the law whereby each thing goes on.
But some men, ignorant of matter, think,
Opposing this, that not without the gods,
In such adjustment to our human ways,
Can Nature change the seasons of the years,
And bring to birth the grains and all of else
To which divine Delight, the guide of life,
Persuades mortality and leads it on,
That, through her artful blandishments of love,
It propagate the generations still,
Lest humankind should perish. When they feign
That gods have stablished all things but fo