Elements as understood as referring to whatever is most basic, that which cannot be broken down further, and out of which all higher-level substances are constituted.
("Atom" as understood in its original sense, and not referring to a certain kind of substance that is made of protons, electrons, and neutrons.)
If it cannot be broken down, then it cannot be destroyed. And if it cannot be destroyed, it must exist? The only way it would go out of existence is if the First Cause were to withdraw His act of conservation. However, even if it exists necessarily, and cannot be destoyred by natural agents, it cannot be therefore concluded that it is eternal? It seems not.
So what is the permament substrate that underlies all material things? Matter-energy is what contemporary physicists refer to, but are they mistaken in putting energy on the same level of reality as substance?
Is it possible for there to be more than one type of element? It would seem so, in order to account for the diversity of things in the world--if there were only one type of element, how could there be difference? Is it possible for one kind of element to be transformed into another kind of element? (If so, how, if there are no parts? How can there be changes in quality without subordinate parts? --How can there be accidents inhering in a substance if there are no parts?)
