Lucretius has many ideas about lots of things like how when you die the soul is "scattered abroad [like when you break a pottery piece], and dies much more quickly. / And the sooner resolved back into its primary atoms [which I think sounds very much unlike a broken pottery piece]" (page 5. Book 3.15)
He also says that primitive man learnt that we should pity the helpless because if they didn't learn that the human race would have been wholly abolished and we wouldn't be here. (Book 5.39)
But I want to focus on his main objective of the poem:
And her first rule for us from this premises shall take its beginning;He cites the objection and then sets out to prove that all came into being without the help of the gods. He claims that naught (nothing of very much importance, something very small) can be made out of nothing. But these small things are not all unified and the same:
"Never did will of gods bring anything forth out of nothing."
For, in good sooth, it is thus that fear restraineth all mortals,
Since both in earth and sky they see that many things happen
Whereof they cannot by any know law determine the causes;
So their occurrence they ascribe to supernatural power.
Therefore when we have seen that naught can be made out of nothing,
Afterwards we shall more rightly discern the thing which we search for:-
Both out of what it is that everything can be created,
An in a way all came, without help of gods, into being. (Page 3. Book 1.6)
As it but normal when each from a fixed seed in a fixed seasonSince trees and animals are different they all must clearly come from a different seed. So it looks like many different small objects can come from nothing. Lucretius doesn't go into that much detail exaclty how, but he just maintains that it wasn't the the gods:
Grows, and growing, preserves its kind: thus telling us clearly
That from appropriate atoms each creature grows great and is nourished (Page 4. Book 1.7)
I would make bold to aver and maintain that the order of NatureThese selected bit of Lucretius poem really hasn't swayed me. I still think that the Greek gods didn't make the universe. I also think that if you consider the universe a closed system (that there is no supernatural involvement), then something can not come out of nothing and so then you are left with the problem that everything exists.
Never by will of the gods for us mortals was ever created... (page 4. Book 2.5)
You can read the whole poem here (by a different translator).