LUCRETIUS - The Nature Of The Universe - Book IV

November 3 2017


My notes on this chapter did included comments such as “outright misogyny” and “being ugly is weird?” - this compilation is one of Lucretius’ weirder assertions.

“On images of things.”

Objects, Lucretius starts, throw off insubstantial shapes such as colours. Those shapes are films which reflect a sensation from the object.

“How flimsy is the texture of those films?”

It is not known. Lucretius also assumes that those atoms must be very small.

There are also films spontaneously generated!”

Clouds, for example.

“In what facility and speed are the films generated?”

Films are constantly emitted it is explained, because the reflections in the mirror are constant. The reason why mirrors show images at all, is because those films can neither pass through the mirror’s glass nor diffract.

“How speedily do the films move?”


“Touch and sight is provoked by the same stimulus.”

The films we see are the reason for seeing at all. We recognize shapes in the dark via air which carries the films towards our eyes; our eyes conceive the object and we can thus determine its distance.

“Why is the image seen beyond the mirror?”

The films of ourselves is pushed by air into the mirror and the mirrors’ film pushes back air towards us.

“Why our right side appears in the mirrors on the left.”

Lucretius explains that the film that is thrown upon the mirror is not intact but thrown back at us in reverse.

“The eye avoids bright objects.”

The force of the sun’s film is so strong that it disrupts the atomic structure of our eyes. Somehow, there is also the problem that bright light contains fire.

“Sufferers from jaundice see everything in yellow.”

Their very own yellowness reflects its films upon them.

When it’s dark, we see objects that are in the light.”

In a curious claim, Lucretius says that black air enters our eyes first, then light air follows which cleans out the darkness. The reason for this, he says, is the finer grain and higher potency of light air.

“Square towers in the distance appear round.”

Films travelling through a lot of air lose their sharp outlines through frequent collisions with it.

  • It should be noted that there are few places in the modern world that have enough horizon around a distant tower to test this phenomenon. I suppose the haziness of a road on a hot day, and similar such distortions, might suffice. The scientist in Lucretius is willing to assert that the films of the tower are not far reaching enough to not be torn apart by the air in between the tower and our eyes and thus appear round; the Epicurean in him however, needs to make it clear that it is only so because of us, not the films of the tower, that it appears kind-of-but-not-really round - had we only tried harder to look, we would indeed see the squareness of the tower. This is a tricky denial of reality and was one of the bigger criticisms made towards the Epicurean school of thought. (Better explained in The Modes of Scepticism: Ancient Texts and Modern Interpretations by Julia Annas and Jonathan Barnes)

“Our shadows appear to move.”

Shadows are air deprived of light. Air moves.

“The one who says he knows nothing, does not know whether even this can be known.”

If a person has no experience of truth, how does he know of the difference between knowledge and ignorance? What originated the concept of truth and falsehood? Where is the proof that doubt is not the same as certainty?

  • Lucretius appears to be questioning the Socratic paradox.

Truth, he continues, comes from the senses and senses don’t lie.

“How does each sense perceive its own objects?”

Visual films are straight-lined, while auditory films are scattered. Pleasant tastes are caused by smooth particles, while unpleasant ones are caused by rough particles that hurt the tongue. The reason why some things are palatable to some creatures but not to others, is the differing shape of their gullets.

“How are nostrils effected by smell?”

Smells come from within an object and are stronger when crushed or burned due to longer atoms.

  • As a fascinating side-note: Lucretius seems to take it for granted that the reader knows that lions hate roosters!

“Where do imaginations come from?”

Imaginations as Lucretius thinks of them, are mythological ideas such as Centaurs. Centaurs & Co can not be however, because their bodies mature and decay at varying speeds. However, the mind plans what it wants to see and thus, we see what we anticipate to see (like in a dream).

“Nothing in our body was born for use, but the thing born creates its use.”

Some examples are given. Ears existed before sound and battles were fought before the invention of spears.

“Everybody seeks after food.”

This is true for all creatures but more for animals, because they are always moving.

“How do we move our limbs?”

  1. imagine it
  2. will it
  3. do it

“The problem of sleep.”

We sleep because our spirit unravells a little over the day, but our mind keeps working.

“What provokes humans is other humans!”

Lucretius is all over the place in this one. Expect weirdness

He makes sure to explain that men are perfect, women are gross (and tricksters!) and nobody should get too attached.

Men and women both enjoy sex and if the woman orgasms, a resulting child will take after her. If the father or both of them reach climax, the child will take after the father. There is also some latent ancestral seed.

He surprisingly admits that men can be barren and explains that this is due to too coarse or too fine seed.

To ensure fruitfulness, one must make sure that ones diet is good and that one has sex doggy-style.

Pro-tip for all women: a wife must starfish, otherwise she’s a prostitute. If a women is rather ugly, she better be charming!