On the Nature of the Universe (Oxford World’s Classics) (32 page)

If you look down its whole length from one end

It gradually takes the outlines of a cone

Quite joining roof to floor and right to left

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Until the invisible apex of the cone is reached.

At sea, to sailors from the waves the sun

Appears to rise, then set and hide its light in them.

This is because they see only sea and sky,

Lest you should readily believe the senses

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Are everywhere confused and undermined.

To landsmen ignorant of the sea a ship

In harbour seems to struggle against the waves

Maimed, its poop broken. For whatever part

Of the oar is raised above the sea is straight

And the rudders above are straight; but the parts submerged

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Below the water appear all broken back

And wrenched and turned flat upwards and so bent

Right back almost to float upon the surface.

And when at night the winds drive scattered clouds

Across the sky, the shining stars appear

To glide against the clouds and pass above them

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On a way far different from their actual course.

And if you place a hand below one eye

And press it, then a new sensation comes.

Everything we see is doubled by our vision.

Two lights of lamps a-flowering with flames,

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Two sets of furniture all through the house,

And men with double faces and two bodies.

When in sweet slumber sleep has bound our limbs

And in deep quiet all the body lies

Yet we seem then to ourselves to be awake

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And move our limbs, and in the night’s blind dark

We think we see the sun and light of day,

That in our narrow room we pass in turn

Over sky and sea, rivers and mountains;

We see ourselves walking across wide plains.

We hear sounds, though the stern silence of night

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Reigns everywhere; we speak, but still are silent.

And many marvels in this way we see

Which seek as it were to break the credit of our senses,

But all in vain, since the most part of them

Deceive because of notions of the mind

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Which we ourselves bring to them, so that things

Seem so be seen which senses have not seen.

For nothing is more difficult than to distinguish

And separate plain things from doubtful things

Which all at once are added by the mind.

Now here’s another thing: if someone thinks

That nothing is known, he does not even know

Whether that can be known, since he declares

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That he knows nothing. Therefore I will spare

To argue a case against a man like this

Who has put his head where his feet ought to be.

And yet, if I were to grant that he does know, then

I ask him this: since you could see no truth

In anything before, how do you know

What it is to know, and what again not to know?

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What gave you the idea of true and false,

What proves to you that there’s a difference,

That the doubtful and the certain are not the same?

You will find that it is from the senses

In the first place that the concept of truth has come,

And that the senses cannot be refuted.

For some standard must be found of greater credit

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Able of itself to refute false things with true.

And what can be held to tell the truth more clearly

Than the senses? or shall reasoning derived

From false senses prevail against those senses

Being itself wholly derived from them?

Unless they are true, all reasoning is false.

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Will the ear be able to convict the eye?

Or the touch the ear? Or taste refute the touch,

Or nose confound it or eye discredit it?

Not so, I think. For each has its own force

And separate power, so it needs must be

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That softness and cold or heat and colour each

Is separately perceived and separately

We see whatever is involved in colour.

The taste in our mouth has its separate power, and smells

Have separate birth, and sounds. So it must be

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That one sense never can refute another

Nor can they possibly convict themselves

Since each must always equally be trusted.

Accordingly whatever at any time

Has seemed to the senses to be true, is true.

And if reason cannot explain the cause

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Why objects seen as square close to at a distance

Seem round, yet it is better that a man

Lacking reason should give a faulty explanation

Than to let slip from your hands in any way

Your grip upon the obvious, and break

The trust upon which all depends, and tear up

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All the foundations on which life is built.

For not only would all reason come to ruin,

Life itself also would at once collapse,

Unless you dare to place trust in your senses,

Avoiding precipices and such things

As must be shunned, and follow the contrary.

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Believe me, all that array of words is vain

That has been massed and deployed against the senses.

Lastly, in a building, if the ruler is crooked

And the square is faulty and misses the straight line

And the level is even slightly unbalanced,

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The whole house then will of necessity

Be wrongly constructed and be falling over,

Warped, sloping, leaning forward, leaning back,

All out of proportion, so that some parts seem

Ready to collapse, and the whole destined to fall,

A victim to the first false measurements.

So your reasoning about things must be false and warped

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Whenever it is based upon false senses.

And now I have no stony path to tread

In showing how the other senses work.

In the first place, every sound and voice is heard

When it has crept into the ears, and then

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Made impact with its body upon the senses.

For we must confess that voice and sound also

Have bodies, since they strike upon the senses.

Besides, the voice often scrapes the throat. A shout

Roughens the windpipe on its outward course.

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For when the voice’s atoms massed together

Make their way out through the narrow passage,

As the mouth is filled the gateway is scraped.

There is no doubt therefore that words and voices

Consist of bodily elements, since they can hurt.

You see also how much the body is worn,

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How much is drawn from man’s very thews and sinews

By a speech that lasts from the first gleam of dawn

To the black shades of night, especially

If the words are shouted, at the top of the voice.

Therefore the voice must be made of bodily stuff,

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Since much speaking diminishes the body.

The roughness of the voice moreover comes

From the roughness of its atoms, and smoothness from smooth.

The atoms that enter the ear are not of the same shape

When the horn bellows with deep and hollow roar

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And the land re-echoes with its barbarous boom

As when swans from the glens of Helicon

With liquid voice uplift their mournful plaint.

When therefore from deep within our body

We force the voices out and send them forth

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Straight through the mouth, the quickly moving tongue,

The cunning fashioner of words, joints them

And moulds them, and the shaping of the lips

Plays its due part in giving form to them.

When there is no great distance for the voice

To run, it follows that the words themselves

Are clearly heard, each separate syllable.

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For the sound keeps its shape and keeps its form.

But if the space between is unduly long,

Words passing through much air must be confused

And the voice distorted as it flies through the air.

And that is why, though you can hear the sound,

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You cannot grasp the meaning of the words,

The voice is so obstructed and confused.

Often one voice can penetrate the ears

Of a whole crowd, when uttered by a cryer.