What Did Epicurus Say About the Nature of the Universe (Physics)?

1. Nothing comes from nothing and nothing goes to nothing, and therefore the universe as a whole has existed eternally, and the universe was not created at any single point in time, neither by a god nor by any other single event.
2. Everything in the universe is composed of combinations of elementary matter and void. Therefore nothing else exists - no Religious "heaven" or "hell," no spiritual or other dimension, no Platonic "ideals," no Aristotelian "essences." Nothing exists except elementary matter, void, and their combinations.
3. The amount of elementary matter and void in the universe is unlimited in extent. Therefore the universe as a whole is unlimited in extent, and the universe as a whole has no center and no edge, and the earth is not uniquely positioned at the center of the universe.
4. The elementary matter is always in motion, and therefore the universe is constantly changing, but not so fast that we are unable to grasp the truths that are relevant to us.
5. The elementary matter moves through the void at a uniform speed, but vibrates in compounds due to collisions, and therefore the change in the universe is not chaotic, but subject to laws of motion.
6. The elementary matter is capable of swerving from its path at no fixed place or time, and therefore not everything in the universe is predetermined from the beginning of time.
7. The elementary matter has varying weights, shapes, and sizes, but the number of these variations not infinite, only innumerable. Therefore the properties of elementary matter and the combinations formed by elementary matter and void are not unlimited, but limited by the properties of the elementary matter and its combinations.
8. Combinations of elementary matter and void are not by nature eternal but are created and destroyed. Therefore while the universe as a whole is eternal, the combinations of elementary matter and void, including the Earth, are not eternal.
9. To the extent that "perfect" combinations of elementary matter and void exist, such perfect things (including perfect beings) neither cause nor receive trouble, because causing and receiving trouble are characteristics only of things which are weak. Therefore to the extent that any life forms, or any combinations of elementary matter and void, have developed the capacity to live without end, they neither cause change to us nor or are they changed by any actions we may take.
10. Nature never creates only a single instance of any kind of thing. Therefore life exists throughout the universe, as the Earth cannot possibly be the only place where life exists.
11. In the Universe as a whole, every thing has its match and counterpart. This principle of uniform distribution is known as "isonomia." Therefore, for example, there are a comparable number of "immortal" beings as "mortal" beings in the universe.

References for this list may be found here.

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