Introduction
The question is, was, and always will be, "what is being?" This question is so immense, profound, and all-encompassing that it is difficult to even know where to start looking for an answer to it. Philosophical experience, however, suggests two other questions in order to get a handle on this, the question of the ages: "what makes this being this being, rather than that being?" and "what makes this being this kind of being?" These questions are the same as asking "what are matter and form?" They are also the same, in effect, as asking "what is sameness and what is difference?"
The various views on matter and form have played a most important role in distinguishing the various philosophical schools throughout history. Aristotle stands or falls with his hylomorphism. Epicurus, together with today's materialist, denies that there is a distinction between matter and form. Berkeley denies that there is any matter at all. Kant's epistemology is built around the idea that the outside world provides matter while form is created by our minds. Plato placed both form and matter in the outside world, but looked to the heavens for form, rather than confounding it with matter in one thing as Aristotle did.
It is with form that this thesis will deal. In true Platonic fashion, however, I will have to wonder down to the consideration of matter and only then climb to the consideration of form. Then I will be better prepared to meet the question of being, but I will have to leave that for my life's work, which must include many more trips down and up.
Thousands of years ago Plato discovered that the form of a thing, what makes it to be one kind of thing rather than another, is a separate distinct being from all individual members of that kind. What makes a thing to be a man, Humanity Itself, is a distinct being from each individual man. Individual men participate in this one thing, Humanity Itself, and derive their own humanity from it. It is in virtue of this one thing, their resemblance to and connection with it, that they are all one kind of being. The same is true for each and every kind of being. I hold, together with Plato, that each and every one of these separated essences is a facet of one Being, Goodness Itself, the Demiurge, or God.
Ultimately a noetic experience is required in order to understand the Forms and how things participate in them. The considerations of this thesis do two things: they manifest the truth of Plato's theory, and they lay the groundwork for understanding it by straining the mind in the right direction. If these mental exercises are engaged in humbly and with trust in God, there is hope that the Christ Within will enlighten the mind as a foretaste of heaven.
There are three parts to this thesis. The first part is a refutation of Aristotle's hylomorphism, specifically his theory of matter. The second part argues that the world is unintelligible without the existence of the Platonic Forms and human perception of them. These reasons include, though are not limited to, the lack of natural substantial forms, as evidenced by the first part; the existence of necessary truths; and the degrees found among perfections. The third part argues that for there to be many things of one kind, there must be some one separate thing in which they all participate.
It is the view of this author that only a revival of Platonism will enable Catholic philosophy to meet the challenges of modern thought. Only a Platonic epistemology, based upon the idea of the Forms, can overcome modern skepticism. Only a Platonic metaphysics can reconcile common sense to modern scientific discoveries and save natural philosophy.
Without Platonism, Catholic philosophy may always be ridiculed as backwards and will always be unable to convince modern man, for Aristoteleanism must turn a blind eye to all the advances of modern philosophy and of modern science since the time of the Renaissance. Catholic philosophy must be apostolic, and therefore to be in tune with the times yet without compromising on the faith. Platonism is always sensitive to new intellectual movements, but it in no way compromises the truth of the Catholic faith, as may be seen by the fact that the majority of the Church Fathers were themselves Platonic.
“If, then, Plato defined the wise man as one who imitates, knows, loves this God, and who is rendered blessed through his fellowship with Him in His own blessedness, why discuss with the other philosophers? It is evident that none come nearer to us than the Platonists."


Part One
Substance and Matter
Natural Philosophy must begin with appearances and seek to explain them. Things appear to change substantially all the time (understanding by substance that which a thing is): what was water has become air. What was wood is now a table. What was decaying organic matter, having been eaten, is now part of a man. Accordingly, it has been the business of philosophers to wonder about this phenomenon. Several have questioned whether things really do change substantially, as they appear to. Others have assumed that they do, and tried to explain how such a thing could occur. The best and the only possible explanation and defence of substantial change was provided by Aristotle in his Physics. This explanation falls apart, however, on closer examination.
Aristotle's belief in substantial change forces him to posit the existence of prime matter, pure potentiality underlying all bodily substances. With prime matter posited, Aristotle was able to take the Forms with which Plato had solved the problem of the possibility of human knowledge, and to place them in matter, in nature. He then turned around and criticized Plato's theory as unable to account for knowledge of nature.
This part of the thesis will expound Aristotle's theory of hylomorphism and demonstrate its impossibility. In this way the ground will be cleared for the next part, which will show how Plato's theory of the Forms is the only way to account for human knowledge, even of nature.

Change à la Aristotle
Aristotle's defence and explanation of substantial change is couched within a broader consideration of change in general, one which is quite helpful. He begins by noting that contraries are essential for any change. A thing cannot become white unless it is not white. It may become white if it is hot or tall, etc., but only accidentally. For if a thing is hot, it cannot become white unless it is also not already white. So what really matters is that the thing not be what it is to become. So all change involves contraries, white and not-white, or hot and cold, etc... These contraries can be true contraries, like hot and cold, or possessions and privations, like white and not-white, but ultimately even contraries reduce to possession and privation when it comes to change. For the reason the cold can always become hot is that the cold can never already be hot, as opposites cannot both be at the same time in the same subject. So ultimately possession and privation are principles of every change.
However, contraries cannot act on each other. Black cannot make white black, for white cannot be black, it is its contrary. Black must make something which is white black. "For friendship does not gather strife and make something out of it, nor does strife make something out of friendship, but both work on some on third thing."
If there is not something else which underlies and persists through a change, either contraries will be each other, such as white being black, or being will come from non-being. If there is not something to receive both white and black, at different times, in the change from white to black you will have white ceasing to be and black coming to be from nothing. But being does not come from non-being. So there must be something underlying every change which persists and receives the contraries. Thus there are three principles to every change: the contrary from which a thing changes, the contrary to which it changes, and the underlying. For example, when a chameleon changes from green to brown, the substance, the chameleon, endures through the change, underlying at first the accident green and then the accident brown. So far, so good.
However, Aristotle believes that ultimately substance cannot be the underlying in a change, for he thinks that substance itself changes. He believes that substantial change, a thing changing what it is, happens physically. Water becomes air, not as a rearrangement of parts, as an atomist would say, but as a change in its essential being. If this is the case, substance cannot be the underlying, for in such a change, no substance persists and underlies. The substance of water ceases to exist and the substance of air comes to be.
In order for this not to be a case of annihilation and subsequent generation from nothing, a physical impossibility, there must be an underlying which is sub-substance, which underlies substance and is before, after, and during the substantial change. This thing is prime matter, receptive of substantial and accidental forms (actualities,) but not itself anything. For if it was an accident, it itself would have an underlying substance, and if it was a substance, it could not be receptive of contrary substances. At the bottom of every natural thing, for Aristotle, there is a being which is without being anything. It always exists in some substance, united with some substantial form, but matter as matter is not anything at all, and yet can become anything.
One cannot state what prime matter is, for it is not anything. (It can be grasped, according to Aristotle, only by analogy, for it stands in relation to substance as bronze does to shape.) Matter itself is not determinate in any way; anything one might say about it would be false. One cannot say what it is, for it is sub-substance, nor what sort of thing it is, for it is sub-quality, nor how much or many it is. There is no such thing as five cubic feet of prime matter, for that would be to be already determined by an accidental form, a certain quantity. The very same (designated or signate) matter can be 1 cubic inch or 10 cubic inches, depending on the forms inhering in it. You cannot even say that matter is one or many, for to be one or any number, to be an individual or individuals, is to actually be a being or beings. Matter is so indeterminate that it can change number by simple locomotion: there is one substance in a pool of water, thus one underlying, yet as soon as someone scoops a cupful out of the pool, you have two substances of water and two matters, oddly enough, where before there was one. All this because matter is not determinate in any way; it is without being anything.
Although matter is not any being, neither is it non-being. Aristotle distinguishes, as one would expect from the previous discussion of the three principles, matter from privation. When a thing comes to be, it comes to be neither from being nor from non-being, but from matter. Matter is of itself neither being nor non-being, but is accidentally each. If a designated matter happens to underlie the form of cat, it is a cat and not a dog, though each of these facts is accidental to it. Later the very same designated matter might become a dog, and no longer be a cat.
Having distinguished matter from privation Aristotle claims that it is not evil. It is not the opposite of good, it is that which desires the good. Matter desires form "as the female the male and the base the noble." It is thus necessary but deficient, just as, according to Aristotle, the female is necessary for the propagation of the species, yet is a misbegotten male. (I feel it necessary not to leave my disapproval of this opinion unvoiced.) Matter's defining purpose is to allow things to come to be, and in doing such, although the essentially imperfect, it fills a necessary role in Aristotle’s natural world.
Aristotle's matter, being neither being nor non-being, yet being receptive of form and desiring it, is potentiality. The three principles of change, before referred to as the contraries and the underlying, have thus emerged as being, non-being, and semi-being, something which neither is nor is not; in other words, the three principles are actuality, privation, and potentiality. Matter is not actually anything but potentially everything, at least everything natural.

Sed Contra
The "existence" of such prime matter is absurd, as it is both unimaginable and inconceivable; prime matter neither is nor is not, or, to speak again, it is without being anything, or, more truly, it is a contradiction in terms. Thus it is proven by reductio that Aristotle was wrong to postulate that substantial change actually occurred; it does not happen (save in a very nuanced way I will discuss later.) Substantial change, as Aristotle rightly deduces, requires there to be prime matter. Prime matter does not exist. Therefore every substantial change necessarily involves something coming to be from nothing, which can only happen by a direct act from God. There is no natural substantial change.
If one will not grant that Aristotle's position is absurd out of respect for a great thinker, (a move which is always questionable, for all great thinkers are capable of thinking the greatly absurd,) one must at least admit that it is the least preferable of explanations. It posits something which is impossible to conceive, on any Aristotelian's admission. For as matter it has no form, no intelligibility. Not only can it not be conceived, it cannot be imagined either. It simply cannot be an object of thought; it is "a certain I know not what" that is posited as fulfilling the needs of a certain theory. If a Christian were to believe in the coming to be of substance, it would be more intelligent to assume that God caused every instance of it directly, for he can create ex nihilo, and no far-fetched matter need be assumed. (This would be a supernatural explanation, an intelligible natural explanation would be some form of atomism.)
In fact, the Judaeo-Christian revealed truth that God created everything, including matter, whether it be Aristotle's prime matter or Democritus' atoms, proves that prime matter must not exist. (Aristotle is to be excused for this, as no Greek thinker was able to get away from the notion that matter was co-eternal with God.) For just as everything that God makes must be good, and is only bad by being less good than originally intended, so too everything God makes must be, and be one, and be beautiful, and be intelligible. Prime matter is none of these, but I will consider only the last. Unintelligibility, just as evil, cannot be a principle of its own, yet the notion of prime matter makes it a separate principle of unintelligibility. God thus cannot make prime matter, any more than He can make evil, and thus prime matter cannot exist in any way. (It must be marked that I do not here claim that prime matter is evil per se, but only unintelligible per se, that is enough.)
A Thomist might reply that the foregoing only proves that matter was not created without form. For matter, though not intelligible through itself, is intelligible through form. This does not suffice, however. For though it may have intelligibility through form, it gives form unintelligibility and is thus a principle of unintelligibility. God not only cannot create pure evil, he also cannot co-create a principle of evil in something good, save incidentally (as free will is only incidentally a principle of evil.) God does not plant seeds of evil in his good works. Prime matter is essentially a principle of unintelligibility, and only incidentally a principle of intelligibility (by providing form a chance to exist). God does not put bits of unintelligibility in his masterful works.
That prime matter is essentially a principle of unintelligibility is established by the fact that things are only intelligible precisely insofar as they are immaterial in Aristotelian doctrine. A form in matter is only rendered intelligible by being removed from it by the action of the agent intellect. Natural individuals are not intelligible, and matter is the individuating principle. Some individuals are intelligible, as angels, but they are immaterial, which only shows that it is precisely matter which is the source of unintelligibility. Moreover, the form an artist possesses in his head is rendered imperfect and unintelligible by coming into being in matter. Such prime matter cannot have been made by God, and thus cannot exist.
Coming back to philosophy, the one thing which Aristotle's doctrine of prime matter does have going for it is that it explains a natural event naturally. However, there are other natural explanations of the natural phenomena which are far more intelligible and common-sensical, thus obtaining automatic preference to Aristotle's explanation, setting aside the foregoing theological disproof and the forthcoming a priori philosophical disproof. The best explanation, the one that both makes the most sense at first and holds up under modern scientific investigation, is that of the ancient Greek philosopher Democritus. He posited that there were invisibly small particles of different sorts which he called atoms. Things appear to change what they are because the particles which make them up are rearranged, producing on a sensible level changes in qualities such as color, smell, and taste. On this account, however, things do not really change substantially, and thus it will be objected that man has direct experience of substantial change.
But does he? One cannot sense essences, only accidents, so one can never sense substantial change. One does sense extreme change of many sensible accidents. This might lead one to suspect that there was a change of essence along with the change in accidents, but it is not necessary that this be the case. Indeed, since it has been shown that for substantial change to take place, either there is an unsensible, unintelligible being without essence, or there is coming to be from nothing, this can hardly be the case. Democritus' account thus wins the day. (It should be noted that there are other entirely natural accounts leaving out substantial change which yet do not require that there be ultimate particles; the case, however, is much simpler if I work with classical atomism.)
To sum up then, we have seen that if substantial change existed, an absurd conclusion would follow, or at least one that is the least natural (according to our nature) and least sensical explanation of a natural phenomenon. The appearances of the natural world can be explained much more naturally without substantial change. We have also seen that revealed truth proves that there can be no prime matter, thus also proving that there can be no natural substantial change. The last nail in the coffin of substantial change is nigh at hand.

Respondeo
or
Substance: A Closer Look
Before coming to a conclusion regarding substantial change one must know clearly what substance is. Semper distinguo. What we treated as one thing turns out to be twofold: logical substance and ontological substance.
Our first notion of substance is that it is the answer to the question "what is it?" When someone asks "what is it?" white would not be a valid answer, while man would. Hence we say that man is a substance and white is not. This is clearly insufficient, however. We must seek the cause that makes one thing an answer to that question and another thing not an answer.
Aristotle is once more helpful in making a beginning. He defines substance as what is not present in another . We perceive that white is in a man, while man is neither in white nor in anything at all (except locally, but that is an equivocal sense of 'in' Substance, then, seems to be a stand-alone being. White is not an independent existence, it requires a man to be in, for it is ultimately just a modification of another being, the substance. Man, as every substance, is a being in his own right, not a modification of some other being. A substance, therefore, is a being in its own right, while an accident is a modification of some other being.
This general account of substance makes for an adequate account of logical substance as well. Anything that is thought of as its own idea, an idea which we can then modify with other ideas, is logically a substance. If I think of a plant, that is a thought all on its own. I can add to it the thought of green, as when I think 'green plant', but green is not its own idea. I am not thinking about green, but thinking green about plant. Green could become a logical substance, such as when I think 'Green is soothing.' Then I am thinking about green; it is an idea in its own right. Pretty much anything can become a logical substance, for one can think about anything. It does not follow, however, that what I think of substantially is ontologically a substance.
How can we judge what aspect of a thing really is a being in its own right, and what aspect is a modification? How do we tell what really is an accident and what really is a substance? There is no doubt that man is a substance and green is not, yet the question is not unimportant as to how that judgment is made.
One might say that what we have to abstract to think of on its own is an accident, while what we need not abstract is a substance. However, just as much abstraction is required to think of substance without accidents as to think of accidents without substance. One cannot imagine white without some body in which it is, so white is an abstraction; one cannot imagine man without imagining him to have some color, so man is an abstraction. Abstraction, then, cannot be the grounds upon which we judge that a thing is an accident or is a substance.
Plato provides the proper criterion for judging what is ontologically a substance in the Timaeus. (Understand substance for 'this' and accident for ‘such’ in this passage.)
"Accordingly, since no one of these ever remains identical in appearance, which of them shall a man definitely affirm to be any one particular 'this' and not another without incurring ridicule? There isn't any, but by far the safest way in treating these things is to proceed thus: Whatsoever object we perceive to be constantly changing from one state to another, like fire, that object, be it fire, we must never describe as 'this' but as 'such', nor should we ever call water 'this' but 'such'; nor should we describe any other thing, as though it possessed stability, of all those which are nominally 'this' and 'that', and suppose ourselves to refer to something definite. For such an object shuns and eludes the names 'this' and 'that' and every name which indicates that they are stable. But that wherein they are always, in appearance, coming severally into existence, and whereto in turn they perish, in describing that and that alone should we employ the terms 'this' and 'that'; whereas in describing what is 'such'; hot for instance or white, or any of the opposite qualities, or any compounds thereof; we ought never to apply to it any of these terms.

That being which endures, remains always the same as it was, that ought to be called 'this thing' and is a substance. That portion of being which comes to be and perishes, alters in time, that is called 'such' and is an accident. If someone presents to us a thing in which much is changing, and asks us what it is, our answer will surely indicate something in it which is not changing. So if substance could change, our answer to the question 'what is it?' would be something underneath that substance which did not change, and thus that original 'substance' would not be a real substance, would not be what something is. If copper and tin can change into bronze, and they do, we must say that they are essentially material bodies, (that is what never changes nor can change in sensible beings.) Tin, copper, and bronze are thus not substances, while body is. A piece of bronze, then, is, on a purely physical level, a material body with that composite of accidents which we call bronze.
Thus substantial change is a priori known to be an impossibility. For the substance of anything is precisely that which does not change in it. If there is no substantial change, there is no reason to hold that prime matter exists. If there is no prime matter, Aristotle's notion of form must be incorrect.

Objection Your Honor!
There are two objections to my conclusion that will inevitably be brought forward. It seems that if substantial change does occur, at all, it requires prime matter. However, while material changes might be explained by atomism, changes of life, say from ensouled animal to dead flesh, seem hard to explain as anything other than true substantial changes. The other objection is that potentiality is required for change, for before a thing comes to be it must be able to be. Prime matter, however, is potentiality, and thus seems necessary. These objections will be dealt with here.
When atoms or elements are gathered and organized and an animal comes to be, and when afterwards the animal dies and leaves a corpse, there are substantial changes of a sort. First there is inert matter, then an animal, then a dead body, i.e., inert matter again. An animal is essentially different from the element carbon. Although such changes are truly substantial, prime matter is yet not required for them, for there is, in all such cases, creation ex nihilo.
To understand changes with respect to conditions of life, consider that in a man's body there is really the substance of carbon, although the man is more than an arrangement of its atoms. The substance of carbon exists before it is organized into a man's body, while the man is alive, and in the corpse after he dies. This can be clearly seen from the fact that the individual atoms in any body still do all the same things that they would do based on their own chemistry, separated from the body, as scientific investigation has shown.
Thus in this 'substantial change' the atoms or elements underlie the change, they are the matter of the change. One does not need to look for prime matter; the change is explained by the fact that atoms act as an underlying and the presence and absence of a soul act as the contraries. Such an atom thus does not change from being one substance to being another, it changes from being one substance merely to being part of another as well.
The soul is created ex nihilo by God at the moment of conception. It thus needs no prime matter to underlie its generation. The soul, its own substance, is also part of the substance man. Its power is to unite billions of separate substances, minute particles, and, without making them cease to be the substances that they always were, make them all participate in the one substance man more intimately and physically than they would participate in any non-living substance. For, besides all the effects proper to them as atoms, they physically do more than their own chemistry allows them to. The soul thus grants to them, as a group, effects which cannot be the result of their interactions with each other while at the same time leaving them all that they already possessed individually and from the accident of their conglomeration.
On such a theory the union of body and soul, both as to nature and purpose, may be explained in a way similar to that in which Aristotle explains the acquisition of virtue in book VII of the Physics. The acquisition of atoms isn't an alteration for the soul, but rather the perfection of its nature, just as the acquisition of virtue is not an alteration of man, but his perfection and the completion of his coming to be. A man is a man without virtue, but not a full man, just so a soul is a soul without atoms, but not a full soul. The soul has certain desires and faculties which cannot attain full satisfaction without a body.
It is sufficient to meet the objection that a theory of soul and body has been presented which is both logically consistent and consistent with the faith, and yet does not require prime matter; the theory need not be fully proven. As it is, the consideration of life and death does not evince substantial change, but rather provides more tools to consider the deep and difficult matter of Platonic participation, which seems to be actually a manifold concept. (The participation of carbon in an animal is more direct and intimate than the participation of carbon in Diamond Itself, as will appear later. Both of these are different, again, from the participation of atoms in Extension Itself.) This consideration must lie outside the scope of this thesis.
Before the second objection, a little review: Aristotle's matter cannot actually be anything, otherwise it would have form itself and not be receptive of all forms. Nor can it be privation, for then it would not be. Aristotle's matter is defined as potentiality, which exists not simply because the thing is not what it is to become, but because potentiality is a self-existing, positive thing, (always with form, yet a separate principle.) This potentiality, or matter, is directed towards and desires form. For this reason Aristotle thinks he has avoided saying that being comes from non-being or from being. A thing comes to be from matter which is neither being nor non-being: not being for it is not actual form, and not non-being, for matter is the potentiality of the thing, not the privation of the thing. Thus potentiality stands half way between being and non-being. It is semi-being.
Must not a thing be able to come to be before it comes to be? To be able to come to be means to potentially be. So is not potentiality, and thus matter, a principle, as Aristotle says? This would open the door back up to Aristotle's idea of form and of substantial change, thus putting Plato's theory of the forms in doubt.
The unease is put to rest by a common sense explanation of potential, rather than that of of Aristotle's which makes it an unintelligible independent principle. Potentiality is really a function of what a thing actually is and the fact that it is not the thing which it is to be. Potentiality is not independent of actuality and non-being. Clay can illustrate this, acting in the same way as atoms do. It is in the actual essence of clay to be very pliable, in its actual substance (taken analogically,) is the power of receiving contrary shapes. Clay must have a shape and no shape is contrary to its substantial actuality. Thus if clay, having this substantial actuality, is not shaped like a pot, i.e., has the privation or non-being of pot, it is able to be or is potentially a pot.
Elements have as part of their form or actual essence the receptivity to contrary local motions, spirits have a receptivity to different thoughts. (It should be well-marked that spirits have potency without matter.) Thus potentiality, or materiality if one will, is simply a part of form, or substantial actuality. There is thus no need to think any of Aristotle's theories concerning matter and form. Nor is there any need to distinguish between essence and Aristotelian substantial form.
Having refuted Aristotle's explanation of substantial change, indeed of matter generally, I am left with a challenge: explain substantial change and fill the vacuum left in the theory of knowledge by the destruction of hylomorphism.

Part Two
Divine Ideas

Substantial Thoughts
Thomists put much emphasis, and rightfully so, on common sense and first impressions, (which makes the doctrine of prime matter even more surprising.) There ought always to be a great deal of uneasiness with any position that says that man's natural way of thinking is inaccurate, unless, that is, it can also provide an explanation as to why men think the way they do and how it really does reflect the truth of the matter, even if not in the way they may have originally thought.
We are in such a difficulty with respect to substance. Most people would, at least at first, say that water, or a barbecue, were what certain things are. I, however, maintain that being water or being a barbecue are accidents inhering in atoms, and are what sort things are rather than what they are, in seeming contradiction to common sense. To solve this difficulty, I must advance some preliminary considerations with regard to artifacts.
Somebody once asked me what a Maglite was. I answered that it was a flashlight. He then asked whether or not it was a weapon as well. I supposed it was. "How about a flower pot? I could just take out the batteries." I thought this was odd at first, but as I reflected upon it I thought to myself: "If a given object can serve any number of functions, why doesn't it become each of the things that fulfill those functions?" I must elaborate.
When man makes something, he re-shapes or re-arranges some material he finds in nature. Gaining a new shape or a new relation is an accidental change. Man puts together a bunch of metal pieces and he gets a car. Logically, 'car' is an answer to the question 'what is it?' Physically, there has been accidental change; mentally there has been substantial change. What were pieces of metal are now a car. How can such an ontological accidental change produce a logical substantial change?
When man makes something, he has an idea beforehand of what he wants it to do and how it is going to do it, and thus also of the general shape of the thing. Through the process of accidental change materials take on the shape of one's idea, and the ability to do physically what one's idea does ideally. A physical body, of the same substance as it was in nature, now resembles one's idea of a non-natural substance. A hunk of metal is a car only in virtue of this relation to an idea of man.
The artificer has put nothing into his material other than a shape or arrangement. Neither a substantial form nor a purpose has been put into the body; for how could man do such a thing? It has its purpose only by our perception of it. If one man sees the Maglite as a flashlight, then it is a flashlight. If another man sees it as a weapon, then it is a weapon. If someone else sees it as a flower-pot, and it can serve as a flower-pot, then why isn't it a flower-pot? Could the purpose of the human artificer somehow make its way into the fabric of the thing? Of course not, his purpose for it is no more valid than anyone else's.
Artifacts thus become something greater than they are intrinsically from their relation to human ideas. One should neither say that a car is the same thing as a hunk of metal nor that a car has no real existence. Rather it can only be what it is in virtue of the complex interplay between the sensible, material world and the conceptual world of man. The case is the same as with music. In the purely material realm, when we hear music, all that exists is a series of vibrations in an instrument and in the air. Vibrations are neither notes nor music. Yet music exists, and is not just imaginary. Music comes into being from the meeting of our soul and locomoting matter.
If natural change is simply artificial change on a smaller level, and not carried out by an intelligent agent such as man, (as the atomic theory proposes,) then its case should also be the same. When water changes to air, the material is re-arranged such that it can evoke the concept of air which men possess and perform all the activities that this concept does conceptually. Water comes to be from the meeting of atoms and the concept of water in our mind.
* * *
These considerations, though obviously true, lead one dangerously close to subjectivism. They might incline one to think that man's perception, his subjective experience, is the ultimate determination of the objective world. For I have claimed that concepts, and not simply the objective world, are the source of our experiences and even, in a way, the existence of things. This is where, at long last, Plato's Forms come in.
Although the physical world only gets its full meaning and existence through our ideas, all men seem to have the same ideas. For how, otherwise, could we communicate? Concepts are not something which man creates, otherwise we would not all have the same ones. Besides, experience suggests that man can only combine concepts he already has, not make new ones. Neither, however, are men born with their concepts, for then they would not be constantly learning as they grew up. Nor are concepts always taken from the material world, (for gold and air are not there to be taken, as has been seen,) but are rather imposed on it. Where do they come from?
Concepts are received by the passive intellect just as proper sensibles are received by the five senses. Not being received from the material world, however, they must lie in an intellect, which is where one would expect concepts to lie. Not arising from our intellect they must lie in a higher intellect, an intellect that could make them objective, as they clearly are. Only God's Intellect fits the bill. The concepts that we use to give meaning to the material world, to make it more than just atoms and the void, are the Ideas of the Eternal Art by which God orders the world He created and directs it to His purpose. Man is the middle term, the means by which the rest of creation fulfills the role intended for it. These Ideas may be called Platonic Forms, and by means of them we participate in God's creation of the world.
Every man thus gains his concepts from the same place, God's Intellect. In this way men come to have the same concepts and to be able to communicate with each other. In this way they also come to understand the objects around them, placed in relation to God and to the rest of the cosmos. On their own these objects have only a scant and impoverished, though essentially intelligible, sort of being, a Cartesian sort of quantitative existence. United with the forms, through man's intellect, they take on a rich meaning and essence.
Armed with the Forms, one can now understand the appearance of substantial change. A group of particles, arranged in such a way that they evoke the concept of water, participates in Water Itself. This group of particles can fulfill, and are meant to by God, the purpose that the Idea of Water fulfills in the Eternal Art. As such, man's perception of them as the one substance water is objective. (For the perception is more like that of music than that of the Maglite: only one Idea can be perceived in the matter at any time.) When they are split up, they begin to evoke the concept of hydrogen and oxygen, and begin to participate in new Ideas in God's Intellect. The appearance of substantial change is thus a physical rearrangement of atoms which causes them to cease participating in one substantial Platonic Form and begin participating in another.
Aristotle's theory has already been ruled out by the disproof of prime matter (and thus his concept of form). The only possibility other than the Platonic explanation is that of Kant's, which has obvious disadvantages. On his view we never learn anything, nor do we ever know anything objective (the noumena). We always had the concepts which we apply to the material world, and we have no reason to think that they in any way reflect objective reality. Kant thus flies in the face of common sense and all of our experiences.
Platonism allows one to oppose all such subjective philosophies with something substantial, objective, and, due to the correlative Platonic epistemology, (the principles of which I may not here expound,) immune to all their criticisms. Nevertheless, neither what modern science has taught nor the accurate considerations which modern philosophy has advanced need be ignored. To develop such a new Catholic philosophy in the light of Plato is just what the Church requires to meet the demands of today's intellectual world.

What is Necessary?
Another argument for the existence of Separate Forms in which the material world participates presents itself. This argument is from the existence of necessary truths, and was actually made by St. Bonaventure. His conclusion is that necessary truths must be founded upon Divine Ideas, as the exemplars of natural things. I will present his argument, given in the Itinerarium, and develop it:
"Our intellect then truly attains a true understanding of inference when it sees that a conclusion necessarily follows from the premises, which it sees not only in necessary terms, but also truly even in contingents, as if a man runs, a man moves. It perceives this necessary state not only in things which are, but truly even in things which are not. For just as, when a man exists, it follows that if a man runs a man moves, so also when one does not exist. Such necessity of inference, therefore, does not come from a thing existing in matter, since it is contingent, nor from a thing existing in the soul, since then it would be a fiction, if it were not also in reality; it comes, therefore, from exemplarity in the Eternal Art, according to which a thing has an ability to interact with and a relation to others according to its representation in the Eternal Art. Therefore, as Augustine says in On the True Religion, the light of everyone reasoning truly comes from that Truth and struggles to attain to it. From which it manifestly appears that our intellect is joined to that Eternal Truth, as, except through that Truth teaching it, it is able to grasp nothing true with certainty. You are able, therefore, to see the Truth which teaches you, if concupiscence and phantasms do not impede you and such clouds do not interpose themselves between you and the ray of Truth."

This passage of Bonaventure's is rich and potent. It contains a powerful argument for the existence of Platonic Forms, and takes a brave stance on epistemology. It also illuminates what it means for things to participate in the Forms. The first two of these points are crucial to the argument. The third, though perhaps the most interesting point, must fall outside the scope of this thesis.
St. Bonaventure's argument for the existence of Platonic Forms, or the "representations in the Eternal Art," is based upon the definition of truth. Truth, in the primary sense, is the correspondence of the mind to reality. If one thinks that Cork is in America, that thought is false, for it does not correspond to reality; if one thinks that it is in Ireland, the thought is true, for it does correspond to reality. If there is no reality to correspond to, a thought or statement cannot be true.
With this in mind Bonaventure's argument can be analyzed. He considers a simple, necessary statement: "if a man runs, a man moves." This statement is necessary, it cannot not be true; it is never not true, nor can it ever not be true. Bonaventure asks one to consider, now, what reality this true statement corresponds to. He presents, and then rules out, two possibilities.
One's first thought is, inevitably, that the statement corresponds to the reality of the running men that one sees on any average day. This thought, however, cannot be true. The statement "running men move" is necessarily true, while sensibly running men are contingent beings. Whether men run or all have their legs cut off, indeed, whether men exist at all or they perish utterly, it is still true that if a man runs, a man moves. If the truth of the proposition in question were founded upon sensibly running men, if they were the reality to which the proposition corresponds, it would cease being true when men ceased running or existing, for there would no longer be any reality for the proposition to correspond to. The same problem holds generally for all material things: material things are contingent and thus cannot be the foundation of necessary truths. The foundation of truth must be sought elsewhere.
The second possibility, an important one for Aristoteleans, is that necessary propositions correspond to something in the mind. The proposition "if a man runs, a man moves" follows necessarily from the concept of running. Since propositions exist in intellects, whenever the foregoing proposition is made, the concept of running exists concurrently, and the proposition corresponds to it. However, that which corresponds only to something in the mind, is a fiction. The proposition "elves live forever" corresponds to what was in Tolkein's mind, but this proposition is fictional. The proposition "unicorns have horns" follows necessarily from the concept of a unicorn, yet it does not seem to be a necessary, eternal truth. Mental concepts can be the foundation of fictional truths, but not of necessary truths.
The Aristotelean will object, however. The concept of a unicorn is not taken from the physical universe, nor are the thoughts of Tolkein concerning Middle-Earth, yet the concept of running is. The concepts of unicorns and elves are fictional concepts, and thus so are the propositions which follow from them. The concept of running, however, is not a fiction, and thus neither is the proposition which follows from it. So might not forms abstracted from matter by the agent intellect serve as the foundation for necessary truths? On this view, the consistency of a proposition with the concepts involved, the abstracted forms, would constitute its truth.
A simple thought-experiment will show the inadequacy of such an explanation. Assume that Separate Forms do not exist, or that they play no part in the created intellect's grasp of truth. Suppose, moreover, that God directly brought an intelligible form, an immaterial actuality, into being in a created intellect, a form exactly such as that which would be abstracted from, say, physically existing gold. Suppose also that God never created gold. Such a case is like that of Descartes' evil genius, and the concept would be fictional, as well as all propositions founded upon it. Yet this case is exactly equivalent to that which would arise if, prior to the complete annihilation of all gold, a man had abstracted the form of gold, and retained it afterwards. The form in the man's mind would be exactly the same, and no gold would physically exist, just as in the evil genius situation. In this case as well, then, any universal propositions founded on such a concept would be fictional. If a proposition corresponds only to a form existing in a created intellect, and not to another, independently existing reality, it is a fiction, regardless of where that form came from. Self-consistency of thought cannot be the criterion of truth.
St. Bonaventure therefore advances another reality, which is eternal and necessary, like the truths whose foundation it is: the Eternal Art, with its Divine Ideas. The proposition "running men move" is true because it corresponds to the Divine Idea of Running Itself, which is always the same. The proposition is thus necessarily and eternally true, for nothing can change its object. Necessary propositions are about Platonic Forms primarily, and only about sensible beings through participation.
It should be noted, at this point, that St. Thomas himself believes in the Divine Ideas, and believes that they are the only foundation for truly eternal truths . This does not mean, however, that they are the subjects of the necessary propositions which mortal men make, nor that the truth which man perceives is of them. God dwells in unapproachable light, and the Divine Ideas are perceived by no man, the Thomist will say. The question thus comes to be about the role the Divine Ideas play in our understanding, and, to some extent, about what it means to participate in them.
The previous section of this thesis has already proved that man does perceive the Divine Ideas. It was shown that man has concepts which he could get from nowhere else but from the Divine Intellect. If man can perceive the Divine Ideas of substances, then why may he not perceive other Divine Ideas? Without such perception, man does not know eternal truths, only contingent ones, for all material beings, no matter how long lasting, are contingent. (In ancient cosmology, there were necessary material beings, but such a cosmology is no longer tenable.) Man would thus know contingent, though at times fairly stable, truths, but no eternal or necessary ones. Without any perception of the Divine Ideas, man's thoughts are all contingent. The very possibility of philosophy, which is of necessary truths, depends on man being able to perceive them.
One ought to hold as a first principle that man knows eternal and necessary truths. It is inconceivable that the truths of geometry, the very truths which one learns when one studies Euclid's Elements, ever did not exist. As such the Divine Ideas must be their subjects, and man must perceive them. Once again Platonic Forms not only exist, but they play an integral role in human knowledge.

The First Degree
Another way in which Platonic Forms take part in our knowledge of the natural world is by giving us a standard with which to judge of more and less among different instances of a quality. The case is similar to the fourth way; Thomas argues that in order for there to be a more and less with respect to being, goodness, truth, nobility, and the like, there must be a greatest being, goodness, truth, and nobility. Other things are more and less good, true, etc., as they more nearly resemble this standard. Similarly, in order for us to know that a thing is more or less good, noble, etc., we must know an exemplary case as a standard by which to judge the others.
The argument works as follows: say one perceives two beautiful things, a sunset and a baby. These experiences are similar but different. Their similarity is sufficient for one to judge that there is a quality which they both have, which one may call beauty. However, their similarity does not itself teach one which, if either, has the common quality more than the other. If one perceives a red thing and a green thing, one is also struck by both a similarity and a difference; the similar aspect we term 'color.' Yet one cannot say which one is more colored than the other, in fact, one is inclined to say that neither is more colored.
In order to speak of having a quality more or less, rather than just in a different way, one must have in mind a standard to which different instances of the quality are compared. One judges how regal a person is by comparing him to a king. If one had a different standard, corporals might be called more regal than dukes; after all, they have some similarity in that quality. Noting their similarity, one could think that regality, the similar quality, is a quality of corporals, and that thus dukes are less regal. As it is, one judges by a different standard, the king, because one understands regality to be the quality which kings have. Other people have a more or less similar quality, and are thus more or less regal.
One does say that the baby is more beautiful than the sunset, not just differently so. How can one do this, simply based on the perceived similarity and difference? One has to either presume that one of the two, the baby or the sunset, is the standard by which beauty is defined, or find some third thing to be a standard. Is beauty the kind of thing that I perceive in the baby? If so, the sunset is less beautiful than the baby because the sunset only imperfectly resembles the baby. Is beauty the kind of thing that I perceive in the sunset? If so, the baby is less beautiful than the sunset because the baby only imperfectly resembles it. Or is beauty the kind of thing that I perceive in some third thing? If so, either the sunset or the baby will be more beautiful, depending on which resembles it more perfectly. The perfection named beauty would be a different thing, depending on which was the case, just as heat would be a different quality if pop-tarts were hotter than engine blocks. How does man decide which instance of a quality to hold as a standard?
God possesses all perfections in the highest degree, and thus all perfections are more or less depending on how far they resemble God, as Thomas believes. God is thus the true standard. If God were not the true standard, one would have to say that God was not the most good, noble, etc., because He is most unlike all other things, including whatever else was taken as the standard, and would thus be least perfect. This cannot be thought.
St. Thomas does not believe, however, that man can know God in this life, and he is thus forced to hold that the standard by which man judges the degrees of a perfecting quality, such as goodness, is other than the standard by which things have those degrees. There is thus a disconnect between our judgments and the reality which they judge. If, on the other hand, as St. Bonaventure maintains and as this thesis has argued, man can perceive Divine Ideas, there is no reason to believe that man does not perceive Goodness Itself, Truth Itself, even Being Itself. Armed with such a perception, man can judge the degrees of created good, indeed of all created perfections, by their true standard. Once again, the Forms alone allow us to know the natural world objectively.

Part 3
What is Sameness?
The foregoing arguments, granting the principle that man can have true, objective knowledge of inorganic substances, necessary truths, and degrees of perfection, prove that there are Platonic Forms of many things and that they play a part in man's knowledge. Thus prepared, I can now argue universally that all things of which a term is said univocally are said so in virtue of some one third thing, e.g., if man is said univocally of Plato and Aristotle, it is so in virtue of Man Itself. This is to answer directly the question "what is sameness?"
It may be taken as a first principle that man is said univocally of Plato and Aristotle. Now for a term to be said univocally it must have the same signification in its uses, just as a name is said equivocally when it has a different signification in its uses, as bat does not mean the same when applied to an animal and to an implement for playing baseball. Thus man must mean the same thing when applied to Plato and to Aristotle.
However, according to Thomas, "Just as the genus, when attributed to the species, implies indistinctly in its signification everything that is in the species in a determinate way, so the species, when attributed to the individual, must signify everything essentially in the individual, though in an indistinct way." This implies that the term man has an equivocal signification when said of Plato and of Aristotle, for, as Thomas says that it signifies everything essentially in the individual, it signifies this soul, or this bone and this flesh, in Plato and that soul, or that bone and that flesh, in Aristotle, which are different.
Individuality is part of the essence of each thing. Plato can never become Aristotle; if he did not have this soul, or this bone and this flesh, he could not be the same substance. In other words, this soul, or this bone and this flesh, are part of what it is to be Plato. Thus essence, considered as intrinsic to individuals, cannot be common or universal, it cannot be said univocally of many.
Either, then, man exists separately from Plato and Aristotle, and is related univocally to each, or man only exists as a universal, as something univocally common to many, in the mind. This latter is Thomas' view. This is untenable, however, for if man was only common to many because the same concept applied equally serviceably to many, it would follow that Plato and Aristotle were only perceived as both men, and not actually so: the form in Speusippus' mind is not really in Plato or in Aristotle.
Since, then, individuality is part of the essence of individuals, for a term to be said univocally of many, it must be said in virtue of some one third thing in which the many participate. This third thing is the Platonic Form or Divine Idea, which is in them both as a cause, (whether as an efficient cause or in another way I leave undetermined). Plato and Aristotle are both men because they each participate in the same Divine Idea, which is numerically one and selfsame. Man, applied to both Plato and Aristotle, signifies participation in God according to the mode of Humanity Itself.
Thus to be the same for created things is to participate in the selfsame Divine Idea; thus also form is a thing's Representation in the Eternal Art of the Creator and Sustainer of the universe. Thus the question which this thesis asked has been answered.

The Sun is in the West Now
The main arguments for the existence of the Forms have now been given. Unchangeable beings are required for universal knowledge, for universals allow no exceptions, and if no being was absolutely unchangeable, there could be an exception to anything. Aristotle, recognizing the inseparability and immutability of knowledge, took Plato's forms and placed them in matter, in a misguided attempt to make nature intelligible all by itself. He maintained, moreover, that Plato's Forms, as separate from the natural world, cannot help man to know it. With this attempted synthesis he confused the material realm with the realm of the Forms and misunderstood both nature and the supernatural.
This thesis has shown that Aristotle's hylomorphism is untenable. It has shown that Separate Forms are necessary if man is to know nature and has thus established also the existence of Platonic Forms. It is time for Catholic philosophers to return to their Platonic roots so that they may rightly understand the natural and the supernatural, rescued from the Aristotelian confusion. I hope that this thesis has started its readers down the path to understanding what the Forms are, in what ways we perceive them, and how things participate in them. Catholic philosophers still have a lot of work to do in developing the theory of the forms, but, for many reasons, this theory promises to meet both the eternal and modern intellectual demands.

Neoteronous