10.Further: If Matter were susceptible of modification, it must acquire something by the incoming of the new state; it will either adopt that state, or, at least, it will be in some way different from what it was.Now upon this first incoming quality suppose a second to supervene; the recipient is no longer Matter but a modification of Matter: this second quality, perhaps, departs, but it has acted and therefore leaves something of itself after it; the substratum is still further altered.This process proceeding, the substratum ends by becoming something quite different from Matter;it becomes a thing settled in many modes and many shapes; at once it is debarred from being the all-recipient; it will have closed the entry against many incomers.In other words, the Matter is no longer there: Matter is destructible.
No: if there is to be a Matter at all, it must be always identically as it has been from the beginning: to speak of Matter as changing is to speak of it as not being Matter.
Another consideration: it is a general principle that a thing changing must remain within its constitutive Idea so that the alteration is only in the accidents and not in the essential thing;the changing object must retain this fundamental permanence, and the permanent substance cannot be the member of it which accepts modification.
Therefore there are only two possibilities: the first, that Matter itself changes and so ceases to be itself, the second that it never ceases to be itself and therefore never changes.
We may be answered that it does not change in its character as Matter: but no one could tell us in what other character it changes;and we have the admission that the Matter in itself is not subject to change.
Just as the Ideal Principles stand immutably in their essence-which consists precisely in their permanence- so, since the essence of Matter consists in its being Matter [the substratum to all material things] it must be permanent in this character; because it is Matter, it is immutable.In the Intellectual realm we have the immutable Idea; here we have Matter, itself similarly immutable.
11.I think, in fact, that Plato had this in mind where he justly speaks of the Images of Real Existents "entering and passing out": these particular words are not used idly: he wishes us to grasp the precise nature of the relation between Matter and the Ideas.
The difficulty on this point is not really that which presented itself to most of our predecessors- how the Ideas enter into Matter-it is rather the mode of their presence in it.
It is in fact strange at sight that Matter should remain itself intact, unaffected by Ideal-forms present within it, especially seeing that these are affected by each other.It is surprising, too, that the entrant Forms should regularly expel preceding shapes and qualities, and that the modification [which cannot touch Matter] should affect what is a compound [of Idea with Matter] and this, again, not a haphazard but precisely where there is need of the incoming or outgoing of some certain Ideal-form, the compound being deficient through the absence of a particular principle whose presence will complete it.
But the reason is that the fundamental nature of Matter can take no increase by anything entering it, and no decrease by any withdrawal: what from the beginning it was, it remains.It is not like those things whose lack is merely that of arrangement and order which can be supplied without change of substance as when we dress or decorate something bare or ugly.
But where the bringing to order must cut through to the very nature, the base original must be transmuted: it can leave ugliness for beauty only by a change of substance.Matter, then, thus brought to order must lose its own nature in the supreme degree unless its baseness is an accidental: if it is base in the sense of being Baseness the Absolute, it could never participate in order, and, if evil in the sense of being Evil the Absolute, it could never participate in good.
We conclude that Matter's participation in Idea is not by way of modification within itself: the process is very different; it is a bare seeming.Perhaps we have here the solution of the difficulty as to how Matter, essentially evil, can be reaching towards The Good:
there would be no such participation as would destroy its essential nature.Given this mode of pseudo-participation- in which Matter would, as we say, retain its nature, unchanged, always being what it has essentially been- there is no longer any reason to wonder as to how while essentially evil, it yet participates in Idea: for, by this mode, it does not abandon its own character: participation is the law, but it participates only just so far as its essence allows.Under a mode of participation which allows it to remain on its own footing, its essential nature stands none the less, whatsoever the Idea, within that limit, may communicate to it: it is by no means the less evil for remaining immutably in its own order.If it had authentic participation in The Good and were veritably changed, it would not be essentially evil.
In a word, when we call Matter evil we are right only if we mean that it is not amenable to modification by The Good; but that means simply that it is subject to no modification whatever.
12.This is Plato's conception: to him participation does not, in the case of Matter, comport any such presence of an Ideal-form in a Substance to be shaped by it as would produce one compound thing made up of the two elements changing at the same moment, merging into one another, modified each by the other.