(Compare Seneca, De Benef. iv. 8.) We can conceive the existence of a thing, or rather we may have the idea of an existence, without an adequate notion of it, “adequate” meaning coextensive and coequal with the thing.  We have a notion of limited space derived from the dimensions of what we call a material thing, though of space absolute, if I may use the term, we have no notion at all; and of infinite space the notion is the same—­no notion at all; and yet we conceive it in a sense, though I know not how, and we believe that space is infinite, and we cannot conceive it to be finite.

[C] The notions of matter and of space are inseparable.  We derive the notion of space from matter and form.  But we have no adequate conception either of matter or space.  Matter in its ultimate resolution is as unintelligible as what men call mind, spirit, or by whatever other name they may express the power which makes itself known by acts.  Anaxagoras laid down the distinction between intelligence [Greek:  nous] and matter, and he said that intelligence impressed motion on matter, and so separated the elements of matter and gave them order; but he probably only assumed a beginning, as Simplicius says, as a foundation of his philosophical teaching.  Empedocles said, “The universe always existed.”  He had no idea of what is called creation.  Ocellus Lucanus (i, Sec. 2) maintained that the Universe ([Greek:  to pan]) was imperishable and uncreated.  Consequently it is eternal.  He admitted the existence of God; but his theology would require some discussion.  On the contrary, the Brachmans, according to Strabo (p. 713, ed.  Cas.), taught that the universe was created and perishable; and the creator and administrator of it pervades the whole.  The author of the book of Solomon’s Wisdom says (xi. 17):  “Thy Almighty hand made the world of matter without form,” which may mean that matter existed already.

    The common Greek word which we translate “matter” is [Greek: 
    hyle].  It is the stuff that things are made of.

Matter consists of elemental parts ([Greek:  stoicheia]) of which all material objects are made.  But nothing is permanent in form.  The nature of the universe, according to Antoninus’ expression (iv. 36), “loves nothing so much as to change the things which are, and to make new things like them.  For everything that exists is in a manner the seed of that which will be.  But thou art thinking only of seeds which are cast into the earth or into a womb:  but this is a very vulgar notion.”  All things then are in a constant flux and change; some things are dissolved into the elements, others come in their places; and so the “whole universe continues ever young and perfect” (xii. 23).