Again, anything concerning creatures that is considered in common by the philosopher and the theologian is considered under different principles. For the philosopher takes his argument from the proper causes of things, the theologian from the first cause. Therefore divine wisdom or theology ought to be called the highest wisdom, since it treats of the highest cause. However divine wisdom sometimes argues from principles of philosophy, just as First Philosophy or metaphysics uses the data of all the sciences for its own purposes.

Similarly, the two kinds of teaching do not follow the same order. For philosophy considers creatures in themselves and leads us from them to the knowledge of God, but theology starts with God and then considers creatures in their relation to God. The order of theology is more perfect, because it more resmebles the knowledge possessed by God, who, in knowing himself, immediately knows other things.

It is, moreover, a sign of perfection for whatever is in act to produce its like; thus God is able to produce other beings, whose existence bears some likeness to his own.

Also, the more perfectly something is actual the farther its power can reach; so God's infinite power can reach to unlimited varieties and numbers of created things.

Hence it is said: "His works are great, past all reckoning, marvels beyond all counting" (Job 5:9); "Each sign we showed them was greater than the previous one" (Qur'ân 43:48).

It is clear that active power is fittingly attributed to God (II:7). For he is the source of being to other things.

Again, the more something is in act─and God is pure act─the greater its active power.

Divine perfection, furthermore, includes the perfections of all things, among which is active power.

Moreover, the fact that God acts and moves other things indicates that he has the power to act.

Thus it is said: "An El too dreadful for the council of holy ones, too great and awesome for all around him: Yahweh God of armies, who is like you? Mighty Yah, your faithful surround you" (Psalm 89:8-9); "God is the creator of everything, and he is the unique and invincible (qahhâr)" (Qur'ân 13:16).

Furthermore, every perfection of God is contained in his very being, and nothing is accidental to him.

Finally, other agents depend on God as the first agent who acts through his very self.

Also, if action is the complement of power, God's power can be completed or fulfilled only by his own essence.

So God's action is in no way accidental to him, but is identical with his power, which is identical with his essence.

Likewise the dependent relationship of other things to God involves corresponding language relating God to creatures.

Further, likeness of other things to himself implies reciprocal likeness to them.

Also God's knowledge of other things implies a kind of relationship. So also does his status as agent and mover of things in the world. And so does his position as the "first" being and "highest" good.

Moreover, as the first measure of all things, God is like the object of knowledge to knowledge, where a real relation is in the knower but not in the known.

Furthermore, God is related to potential beings in the same way as to actual ones, and in the first case this relationship cannot be real.

Besides, some of these relationships are not eternal, such as Lord or Creator; if they were real they would imply a change in God, which is impossible.

Neither can it be said that those relations exist somewhere outside God (II:13-14). For if they did, we should have to consider yet other relations of God to these realities, and so on endlessly. Therefore, these relations are attributed to him solely in accordance with our manner of understanding.

It also follows that such relations are not said of God in the same way as other things are predicated of him. For all other things, such as wisdom and will, express his essence, while the aforesaid relations do not, but only express our way of understanding.

However, our understanding is not fallacious. For from the very fact that our intellect understands that the relations of the divine effects are terminated in God himself, it predicates certain things of him relatively.

Moreover, these many relations, which do not signify God's essence, do not contradict God's simplicity. Rather, the more something is simple or undivided, the more perfect and powerful it is, so that more and more things are related to it, and this is most true of God.

This can be seen also by the fact that things of the same nature come into existence and go out of existence, while the nature remains the same. Therefore existence is dependent on an outside cause which is being in the highest degree, necessarily existing, fully in act and perfect.

Again, the order of causes necessarily corresponds to the order of effects, since effects are commensurate with their causes. Now, being is common to everything that is. Above all causes, then, there must be a cause whose proper action is to give being, and this is God.

Moreover, only God is identical with his existence, while all else exists by participation, possessing a created existence deriving from his.

So we hear that "He made heaven and earth, the sea and all that is in them" (Psalm 146:6); "Your Lord is God who created the heavens and the earth in six days and then mounted the throne, making night cover the day as it eagerly pursues it, while the sun and the moon and the stars are subject to his order" (Qur'ân 7:54).

Also, because God is the fulness of act, he is prior to the potentiality of matter; therefore he can produce the totality of a thing, whereas every other agent is only a partial cause, bringing a form out of pre-existent matter. So we read: "In the beginning God created heaven and earth" (Genesis 1:1); "Your Lord is God who created the heavens and the earth in six days" (Qur'ân 7:54).

It is, therefore, an error to assert that matter has no cause whatsoever. This error is based on the observation that in the actions of particular agents there is always an antecedent subject underlying the action, and so it is assumed that from nothing comes nothing. This is true of particular agents, but not of the universal Agent which is productive of being in its totality, for his action presupposes nothing whatever.

Also, bodies do not act by the totality of what they are, but by specific powers that they have; therefore their effectivity is restricted to producing specific forms or dispositions in a thing, not the total thing.

Furthermore, the greater the power of an agent, the further does its effectivity extend; since the distance between being and non-being is infinite, an infinite power is required to create, and this cannot be contained in a body.

Again, a body must come into contact before it can act on another; this pre-supposes the existence of the other, which excludes creation.

Also, God is the universal cause of everything, but directly and properly of of existence, which is a universal effect common to everything; but to cause existence is creation, since it presupposes nothing pre-existent.

Furthermore, to be the author of existence includes being the author of the nature or essence of a thing; but particular agents do not produce any nature as such (e.g. as dog-ness), but only individuals of that nature (e.g. this or that dog), and they do so as instruments of the First Cause.

Again, any instrument acts dispositively to produce the effect intended by the primary cause; thus to be an instrument of creation would imply a pre-existing disposition to existence, which is impossible.

Once again, any natural agent is determined to replicating its own specific or generic qualities, but it presupposes and does not produce the individual existence by which the object of its action is distinct from itself; this is reserved to the Creator, who has within himself the likeness of every being.

A natural agent, moreover, in making something new, is per se the cause only of the new form, and only accidentally the cause of its existence, since it made it out of something pre-existent, unlike the Creator. Thus not even an angel can create anything.

So we read: "In the beginning God created heaven and earth" (Genesis 1:1); "He created everything" (Qur'ân 6:101).

Therefore the opinion of Plotinus and Ibn-Sînâ that God can directly create only one thing, and this in turn creates others, is ruled out. So God is called omnipotent or almighty: "Yours, Yahweh, are greatness and power, splendor, triumph and glory. Yours, Yahweh, are all heaven and earth; you are king and ruler of all" (1 Chronicles 29:11); "God is the owner of the heavens and the earth, and God is omnipotent" (Qur'ân 2:189).

First it must be shown that creation from eternity is not necessary (II:31). If it was necessary for any creature to have existed from eternity, such necessity would either be from itself, in which case it would have to be the first being or God and no longer a creature, or from another. In that case we would have to suppose that God created of necessity, which we have seen to be false (II:23), or that God needs the creature, which is false because he is an all-sufficient end to himself (I:75). Therefore the existence of creatures depends on the free will of God, who is under no obligation or compulsion to create anything. Rather, any necessity found in creation is in relation to other created causes and not to the First Principle of all; for instance, if someone is running he must be in motion, but it is not necessary for him to be running.

2) If he were not always creating, some prior agent would have to move him to create. ─ God action is eternal, but his creatures are not, because he creates voluntarily. That means that things begin to exist when he decided them to exist.

3) If God is the cause of creation and creation does not immediately follow, it would mean that he is not a sufficient cause and must have something added to him from outside to create, and that is impossible. ─ The proper effect of God's will is not for things to exist as long as his will exists, but to exist when he wishes them to be.

4) A voluntary agent does not delay action unless he is waiting for something to mature, either in himself or in outside conditions; but whatever God wills he willed from eternity, nor is anything lacking to his power, nor was there anything to wait for on the part of creatures; therefore he had to create from eternity. ─ The fulfillment of God's will is not delayed, but things come to be when he decided from eternity.

5) If there is no difference in objects there can be no choice of one over the other; but no one moment is preferable to another to begin creation; so creation must either be always or never. ─ Before creation there was no time or moments to choose from; the only choice is between creation from eternity or creation with a beginning point.

6) The purpose of creation is God's own goodness; if his goodness is eternal, then it seems creatures should also be eternal, since they always have the same relationship to God's goodness. ─ God's goodness is the purpose of creatures, but not in the sense that he has anything to gain from them; so his necessary love of his own goodness does not determine when he should choose creatures to exist.

7) God's goodness gains nothing from creatures, but they manifest it according to their degree of perfection; the more permanent their existence, the more they manifest God's goodness; so it seems some creatures should have existed from eternity. ─ On the other hand, it is fitting that creatures should have begun in time to illustrate the infinite distance between creature and Creator and the dependence of all creatures on him and his free will.

2) The power of spiritual creatures and of matter itself is to exist always; therefore they should always have existed. ─ Again, such power presupposes the fact of their coming into existence, which itself was not necessary.

3) Every motion is either preceded by another motion or it is eternal, and if there always was motion then there always was something mobile; so the universe must be eternal. ─ Something can be moved without a previous motion on the part of God or of the thing, according to God's eternal will that such motion should have a beginning.

4) Species are naturally perpetual, while individuals come and go. ─ Such perpetuity presupposes that the species already exist.

5) Time must be from eternity because the point in time called "now" is both the end of the past and the beginning of the future. ─ It is not of the nature of a point always to be in the middle; it can be the beginning of a line (or of time) without being the end of something previous.

6) If time is not eternal then there must have been a "before time began", but time, being an accident, presupposes an existing mobile subject. ─ Before creation there was no time; the "before" refers only to imagined time, just as when we say "outside the universe" we are referring to imaginary place.

7) Some scientific truths are always true, but they are not God; therefore something other than God must be eternal. ─ Such truths, having an attribute necessarily predicated of a subject, have their reality either in the existing things of which they are true (which do not necessarily exist), or in the divine mind.

2) Any becoming is the result of motion, which must be in a mobile subject; if the chain of becoming is not infinite, we come to a first subject that always existed. ─ Creation is not really a change, which is coming from something, so that there is no need for a pre-existing subject which which was different and changed into a new thing.

3) Anything that comes into being must have been possible; such possibility requires a subject; thus again there is either an infinite series of becoming or some first thing that always existed. ─ Likewise, no passive potency pre-existed creation; there was only the active potency of the Creator and the logical potency that such a being was not self-contraditory.

4) The act of becoming presupposes a pre-existing subject in transition; so there must have been an infinite series of becoming or a first thing that always existed. ─ Only coming into being by way of dispository motion presupposes a subject, but creation is a coming into being without motion.

So it is not necessary to say that the universe always existed. Thus we read: "In the beginning God created heaven and earth" (Genesis 1:1); "He created everything" (Qur'ân 6:101).

It is important to reply to attempts to prove that the universe is not eternal (II:38), lest a matter that we believe on the basis of revelation appear to rely on flimsy philosophical arguments. These are as follows: 1) God is the cause of all things, and causes must exist before their effects. ─ This is true of causes that operate through time and motion, but not of a cause that operates instantaneously.

2) All being was created by God from nothing, and this means having existence after non-existence. ─ The nothing that being was created from is not necessarily a previous non-existence but could simply mean that a being that always existed depends on God for its existence without ever having come from anything else.

3) If the universe always existed there would be an infinite number of days or revolutions of the earth. ─ A successive infinite number is possible, because only a finite number actually exists at one time.

4) The continued existence of time would mean that an finite addition to an infinite number. ─ Eternal time is infinite in the past, but finite in the future; so an addition can be made to such time under the aspect that it is finite.

5) If the universe always existed there would be an infinite series of efficient causes. ─ An infinite series of agents is impossible only when they are directly or per se dependent, but in causes that do not act together an infinite series is possible, such as a chain of generation within a species.

6) An actual infinite number of human souls would would exist. ─ Different philosophers gave different bizarre solutions to this question, some saying that there is only one soul that remains, others that there is cyclic reincarntion of souls. But it is not impossible for there to be an actual infinite number of souls since they do not have any order or dependency on one another.

On the other hand, one of the plausible reasons given above for creation in time is that God's goodness is best shown by the fact that nothing but himself is eternal. So there are no cogent reasons for the eternity of the universe or for its temporal beginning. The fact of creation from a point of time is something we hold by faith alone.

The same can be said of the distinction of species in material things, since this distinction comes from the form and not the matter, which is subject to variability.

Similarly, things were distinct at the beginning of creation, where the randomness of matter had no role to play.

Also, the regular (as opposed to chance) motion and activity characteristic of different natural species indicates that these species themselves do not have a random origin.

Finally, if God is the author of the universe and intended its universal good, he must have arranged the distinction and order of its parts.

Thus we read: "God divided light from darkness... God saw all that he had made, and indeed it was very good" (Genesis 1:4,31); "Praise be to him who created all the pairs of males and females among plants of the earth, among men themselves and among creatures they do not know of. Another sign for them is the night from which we detach the daylight, and then men are in darkness. And the sun runs to its fixed place according to the determination of the Mighty and Knowing. We have determined stations for the moon until it returns like an old palm leaf. The sun is not to join the moon, nor the night to come early upon the day, but each follows its own course" (Qur'ân 36:36-40).

Thus we reject the opinion of the ancient philosophers Democritus and Leucippus who reduced all the distinctions of nature to atoms that float freely until by chance they cluster in various configurations. The same criticism applies to an evolutionary theory that sees no stability in nature and no need for intelligence in the evolution of new species.

Also, the agent and the form it intends are the primary determinants of what a thing will be; matter takes its shape from form, rather than the disposition of matter determining what the form will be; an exception is deformity, which results from the resistance of matter to the intention of the agent.

Besides, since matter, like everything else, is caused, its distinction is likewise caused by another and does not come from itself.

Finally, God, being an intelligent agent, orders lower things to be of service to higher things, in this case, matter to form; so specific differences do not result from differently disposed matter, but material differences result from different forms.

The main opposite opinion is Manichaean dualism, which posits two opposite principles of the universe, one good, the other evil. This position runs into the difficulty that if good things have to come from a source that is per se good, then evil things have to come from a source that is per se evil, but such would be a non-being, since evil is privation.

Also, evil, in so far as it is evil, is non-being and cannot act.

Likewise, evil as an effect has no cause except as it happens to be in something existent, which is good and has a cause.

Also, from the point of view of finality, evil as such cannot be intended, but only as it happens to be joined to something good.

Furthermore, contraries are the result of a single action, such as the generation of one thing which is the corruption of another.

So we read: "I am Yahweh, and there is no other; I form the light and I create the darkness; I make well-being and I create disaster" (Isaiah 45:6-7); "Every life tastes death, and we test you with evil and good as a trial; then you return to us" (Qur'ân 21:35). To "make disaster" or evil means making things which are good in themselves but harmful to others, such as wolves or mosquitoes.

Moreover, any secondary agents in the universe act as subsidiaries to the First Agent for the purpose of bringing about the order and good of the universe; thus the First Agent, who has the plan of the whole universe, can immediately cause many different things. The simplicity of God, rather than limiting his effectiveness, is the reason why his power can reach infinitely different effects. Thus we read: "In the beginning God created heaven and earth..." (Genesis 1:1); "Praise be to God who created the heavens and the earth and set up darkness and the light" (Qur'ân 6:1).

Moreover, an angel would have to work with pre-existing things that are already formed, just as the generic agents of this world (such as sun, rain, wind) contribute to the generation of new individuals within pre-existing species, but do not make new species. Individuals of the same form are the proper causes of new individuals within a species, but the form itself, like existence, which belongs to an individual through its form and not its matter, is the proper effect of the First Cause.

Also, through their specific forms things have a likeness to God who is pure act, and likeness indicates the source of a form.

Thus we read: "God said, 'Let the earth produce every kind of living creature in its own species: cattle, creeping things and wild animals of all kinds'" (Genesis 1:24); "God created every sort of beast from water; some of them move on their stomachs, others on two feet, others on four feet. God creates what he wishes" (Qur'ân 24:45).

Also, any difference arising from free choice is accidental to an intellectual creature and cannot determine its species. According to this opinion, therefore, all intellectual creatures, angels and men, would have to be of a single species, which is false.

Similarly, if the kind of body a soul is united to is the result of a previous choice, its union with the body would be an accidental addition to the complete nature it already had.

By the same reason a soul could continue to merit or demerit a better or a worse body, and thus transmigrate, which is not only against the Faith but also philosophically impossible, because determined forms require determined matter.

Moreover, Origen would have to explain how, if all spirits were created equal, they were different from one another before making any choice. It cannot be because of quantified matter, which only distinguished bodies. Therefore it would have to come from form; but no form is distinct from another unless by species.

Besides, if rational creatures do not need bodies, bodies are superfluous for their existence and differentiation; but if they do need them they should be created with them.

Also, the difference between a rational animal and a pure spirit is greater than any differences among pure spirits. Thus natural differences made by God are greater than any supposed differentiation of spirits resulting from their choice.

Furthermore, if the supposed equal spirits all made equal choices, then the material world corresponding to them would have to be all of a single form, which would not well reflect God's goodness.

Also, the opinion that spirits fall into such and such a body because of their sins implies that matter is evil, as the Manichaeans held. But of material creation we read: "God saw all he had made, and indeed it was very good" (Genesis 1:31); "Blessed be God the best Creator" (Qur'ân 23:14).

Moreover, such creatures participate in God's providence by communicating goodness to others by way of planning and free choice.

Above all, they participate in God's goodness by having him as an object of their knowledge; and as his knowledge includes all creatures as well, so intellectual creatures imitate him by the breadth of their knowledge.

Moreover, physical things are corrupted when they receive the form of another, but an intellect is only perfected by receiving the forms of all the things it knows.

Besides, forms received in matter must be particular, but those received in the intellect are universal.

Moreover, the intellect can know some things which are not bodies, and its knowledge is potentially infinite, which could be true if it were a body.

Also, an intellect can reflect on itself and stay there; a body is not capable of such immanent action.

So the word "spirit" is sometimes used of the imperishable part of man, as in the case of the girl who was raised from the dead: "And her spirit returned and she got up at that very moment" (Luke 8:55); "He created man, starting from clay... then he shaped him and breathed into him from his spirit, giving him hearing, seeing and inner organs" (Qur'ân 32:7-9).

Also, an intellect cannot be individuated by matter, since it knows things by uniting with their forms abstracted from individual matter.

Likewise, the action of something composed of individual matter and form would have to terminate at something similarly composed, but the object of intellectual knowledge is abstract from individual matter.

Thus the intellect does not physically become what it knows, but the forms of things exist in the intellect in an intelligible way. This permits contraries, such as hot and cold, to co-exist in the mind, which is impossible in material nature. So the intellect receives the forms of the things it knows without any disturbance to itself, but is rather perfected and finds rest in this knowledge.

So we read: "Wisdom is brilliant, she never fades. By those who love her she is readily seen; by those who seek her she is readily found" (Wisdom: 6:12); "God is the one who does alât over you and over his angels to bring you out of the darkness to the light" (Qur'ân 33:43).

In intellectual substances, which are not composed of matter and form, the very form is a subsistent substance and is the thing that exists. But in material things there is the double composition of matter and form and of essence and existence. Thus some things are common to all created substances, such as reception and perfection, while others are proper only to material substances, such as generation.

Also, the form of a thing is the principle of its existence. A substance can lose its existence by losing its form, but if the substance is a subsistent form it cannot lose its existence, since no thing corrupts into nothing but into potency, and for it to go back to potency would mean for it to be a substance without existence, which is impossible.

Also, just as prime matter is incorruptible, so are immaterial substances, since both are prime potencies in the composition of being.

Besides, intellectual substances are not subject to motion or contraries which would corrupt them as in the material world, for contraries can co-exist in the intellect.

Likewise, corruption is the termination of sensible alteration and wearing down, which can only happen to bodies.

Also, the intellect cannot be compared to the senses which are corruptible when their physical organ corrupts or their object is too intense, like blindness from looking at the sun; for the intellect has no organ, and the greater the things it knows the better it can know lesser things.

Furthermore, what is intelligible is the perfection of the intellect and is commensurate with it. Since everything intelligible is as such incorruptible the intellect must also be so.

Also, there is a natural appetite in everything to resist corruption and continue in existence. Animals have sense experience of existence here and now. They unknowingly provide for the continuation of their species and knowingly resist destruction. But those who understand what perpetual existence is naturally desire it, and this desire cannot be in vain.

Finally, things cease to exist by the same powers that brought them into being. But intellectual creatures came into being by direct creation. Any potency to non-being is not in themselves but in God, who does not destroy what is proper to a nature.

So we read: "Praise him all his angels... Alone he commanded and they were created. He stationed them from of old forever; he gave a decree which shall never pass away" (Psalm 48:2,5-6); "The guardians of Paradise say to the elect, 'Peace to you! You have done well; enter here and stay forever... And you will see the angels encircling the throne and singing the praises of their Lord" (Qur'ân 39:73,75).

Likewise, in a mixture the parts do not keep an actual but only a virtual existence, but intellectual substances are incorruptible.

Nor can it be joined to a body by way of contact, since only bodies can contact one another when they touch. For the same reason it cannot be joined by way of continuation or composition or attachment, since all of these imply bodily contact.

One possible way an intellectual substance can be joined to a body is by way of action; such action involves touching without being touched and acting without being acted upon. By this contact of power an indivisible intellectual substance can touch the whole divisible surface of a body, which a bodily point cannot do; not only that, but it can penetrate the whole body and not just the outer surface. Such a union of an intellectual substance with a body is not a substantial union, but as a mover to a distinct thing being moved.

To have substantial union with a body, an intellectual substance would have to be its substantial form; anything else would be an accidental union. But to this possibility there are many objections:

1) A body and an intellectual substance are both complete substances, so cannot be made into one. ─ They are not two actually existing substances, but one; the soul makes the body actually exist.

2) Matter and form should be in the same genus, but an intellectual substance and a body are different in genus. ─ Matter and form are not species of the same genus, but principles of the same species, as is true of the body and the soul when they are united.

3) The intellectual substance would no longer be immaterial if it were the form of a material body, since its existence would correspond to the form as it is in matter. ─ The human soul is not immersed in matter or entirely absorbed by it, but has its own immaterial existence which it shares with the body.

4) Anything whose existence is in the body cannot be separated from the body the way the philosophers say about the intellect. ─ The intellective soul is also the principle of the vegetative and sensitive operations of the body, and these powers of the soul are the forms of bodily organs; yet the soul's intellective power operates without a bodily organ and is therefore called "separate", together with the soul itself, which also actualizes and gives existence to the body.

5) Something whose existence is common with the body must act in conjunction with the body and not transcend it in action; thus intellectual action is impossible. ─ To be the act of the body does not limit the soul from other actions transcending the body, just as it transcends it in existence.

But this is impossible, since the contact of a soul merely by power cannot make a body vegitative and sensitive.

Also, besides intellective action, there are some actions like anger and sensation which involve both the body and the soul, but that would be impossible if the two were not substantially joined. Plato tried to say that these actions belong to the soul as mover and to the body as something moved, but this answer runs into the difficulty that sensation is a movement of the sense by a sensible object, not by the soul; the senses are passive powers in bodily organs, requiring a substantial union of body and soul.

Also, if the soul is the agent in sensation, as Plato says, even irrational animal souls will have an operation that is distinct from the body, and they would therefore survive the destruction of the body.

Moreover, according to this position, a corpse would not essentially differ from a living body.

Likewise, death would not be the corruption of anything, but a parting of two already separate substances.

Also, if the distinct soul is free to move or not move the body when it likes, it could just as well separate from the body and come back to it any time it likes.

But the human soul is the form of the body, since by the soul the body actually exists and lives.

Also, being and action belong to the composite; thus we say that a man is healthy ─by reason of body─ and knowlegeable ─by reason of soul─ or living and sensing ─by reason of the two together. A sensitive soul is related to the whole body as its sensitive powers are related to distinct bodily organs, of which they are the act; thus the soul, which is also sensitive, is the act of the body.

Moreover, he would be three substances, not one; what is basically a living vegetable would have added accidentally to it a sensitive and an intellectual soul.

Also, if man is a soul using a body, Plato should say which of the three souls; if it is the intellective, then it is a soul using an animal, since the body is animated with a sensitive soul.

Again, if man were to have several souls and a body, there would have to be something that unites them all; nothing could do this except a single soul which is the single substantial form.

Besides, each separate soul ought to have a special place in the body, as Plato says, the intellective in the brain, the sensitive in the heart and the nutritive in the liver (Timaeus); but the intellect does not have an organ, and the nutritive function is found everywhere in the body, as is apparent when plants are divided.

Finally, any intense activity, such as thinking or sensation or digestion etc. weakens the other activities of a person, which shows the unity of the person that comes from one principle, the soul.

1) They quote Aristotle, who said that it is "separate", "not mixed with a body", "simple" and "impassible" (De anima, III, ch. 4, 429a 12─430a 6), which could not be said of the form of a body. ─ Aristotle's demonstration concludes from the nature of the operation to the nature of the principle of operation, which is the intellective power operating without a bodily organ. That does not prevent the intellective soul from also being the form of a body.

2) It must be in itself empty of all forms so as to be capable of receiving the forms of everything, but if it is the form of a body it would share in corporeity and thus not be empty. ─ The union of the soul with the body does not make its intellective power the act of a bodily organ; thus it remains in potency to receive all intelligible forms.

3) If it is the form of a body it must receive forms materially and individually; therefore it could not know universals. 4) If the possible intellect received forms like prime matter, it could not know anything. ─ The answer to both these objections is that the intellective power is not the act of any part of the body.

5) The possible intellect is potentially infinite in its knowledge, but an infinite power cannot exist in a body. ─ The infinite power of the intellect is founded in the nature of the intellective soul, which is immaterial.

Holding, because of these objections, that the possible intellect is separate from individuals and common for all mankind, Ibn-Rushd tried to show how individual men understand. And he said that our imagination comes into contact with this possible intellect when it comes into contact with any intelligible forms. ─ This position, however is ridiculous because only someone having an intellect can be said to understand; the contact he posits would only make the person understood by the separate intellect.

Also, the contact of the separate possible intellect with the phantasms of our imagination would only make the phantasm an object of understanding, not the subject, since the intelligible species that informs the possible intellect is related to the phantasm as the visible species that informs the eye is related to the outside object; and the outside object, for example, a stone, does not see but is seen. So a man who understands is related by his intellect to an intelligible object; it is not the object that is related to him.

Likewise, the principle of any action must be a form in the thing, and the possible intellect is the principle of our understanding.

Also, for an intellect to be in act is to have an object intelligible in act, just as to have a sense in act is to have something actually sensed; but a phantasm is not actually intelligible, but only when an intelligible species is abstracted from it; so it cannot be a medium of contact between us and a separate possible intellect. Even when the agent intellect makes the object actually intelligible, this object is not actually understood until it is impressed on the possible intellect.

Furthermore, a higher operation is an indication of a higher kind of life and a higher kind of soul; so intellectual operation is an indication of an intellective soul.

Moreover, such supposed contact of the imagination with a separate possible intellect is subsequent to the existence of the person; thus the person would not differ essentially from an irrational animal.

Finally, according to this position a child in the womb who does not yet have phantasms would not be human, because he is in no way rational.

Again, a child understands potentially before he comes of age; therefore he is not in contact with an outside possible intellect through a an object actually understood but has a possible intellect as part of himself right from the beginning. Ibn-Rushd replies to this argument saying that a child understands potentially, first because his phantasms are potentially intelligible, and secondly because he can come into contact with the separate possible intellect. ─ But, as for the phantasms, understanding is the passive reception of an intelligible form, whereas making phantasms actually intelligible is an action affecting the possible intellect.

Also, the power to understand follows upon being human, but having phantasms does not make someone human.

As for coming into contact with a separate possible intellect, no one can be said to understand potentially without having a power to understand.

Also, a child's potency to understand is not like a stone, with no principle of understanding, but like a car ready to go as soon as it is fueled and the ignition is turned on.

Furthermore, if understanding is the act of the possible intellect, then the habit of science is also in the possible intellect; but science is something in us, qualifying us as knowledgeable, and this cannot be in the cogitative sense, because it has to do with universals and is the product of the agent intellect.

Moreover, the possible intellect by nature depends on sense knowledge to know anything; therefore it is part of man and not something above him. A sign of this is that the intellect does not directly know separate substances, but sensible substances directly and separate substances indirectly and always using phantasms. Otherwise its knowledge would be purely angelic and the senses would be superfluous, because an intellect could not know sensible and spiritual things without some order: either the spiritual through the sensible or the sensible through the spiritual.

Although he claims the authority of Aristotle, Ibn-Rushd's opinion is not in agreement with Aristotle (II:61), since Aristotle defined the soul as "the first act of an organic physical body potentially possessing life" (De Anima, II, 1, 412 28), and this definition applies to every soul. Later he says that "there is nothing to prevent some parts being separated, because they are not actualities of any body" (II, 1, 413a 7). As for the statement, "In the case of the mind and the thinking faculty nothing is yet clear; it seems to be a distinct kind of soul..." (II, 2, 413b 25), this does not contradict the generic definition of a soul, but merely shows how it is different: "it alone admits of being separated, as the immortal form the perishable" (loc cit.). He goes on to list the intellect among the powers of the soul: "Of the faculties of the soul... we have mentioned those for nourishment, for appetite, for sensation, for movement in space, and for thought" (II, 3, 414a 32). Elsewhere he calls the possible intellect a part of the soul: "Concerning that part of the soul by which it knows and thinks..." (III, 4, 429a 10). He goes on to say: "By mind I mean that part by which the soul thinks and forms judgements" (III, 4, 429a 23).

The soul is also adapted to a particularized body, and cannot fit any other body, either as a form or as a mover.

Moreover, each being has its unity from its form and could not be distinct from others if they all shared the same form; this form in man has to be intellective, since that is the operation that makes man a man. Ibn-Rushd's position would amount to there being just one man, the separate possible intellect, and many irrational animals (the men we know) whose phantasms are in contact with the mind of this man. The phantasms of the imagination, however, being accidental perfections, are many and transient and cannot define any species. Neither the imagination nor the cogitative sense can understand or make man any different from irrational animals.

Besides, each person has his own knowledge and his own act of understanding which is not that of another person; the varying dispositions of people's exterior or interior senses are only a remote disposition to their intelligence, whereas science comes directly from mastering principles and drawing conclusions.

Again, if there were one intellect for all mankind it would have to have been in contact with the agent intellect and known everything from eternity, if it is eternal; thus it could learn nothing new, and all sense experience would be superfluous, whereas the intellect needs phantasms to learn and also actually to consider what it knows.

Ibn-Sînâ thought that the possible intellect is stimulated into contact with the agent intellect by looking at the phantasms stored in the imagination. ─ This is contrary to what we would expect, since we are more disposed to receive inspiration from separate substances by being abstracted from sensory influence.

Plato was more consistent in saying that we have all knowledge in our intellects from the beginning, but separate forms help to purge our intellects from obstacles to remembering this knowledge.

Moreover, we should expect the intellect to be able to store knowledge, since it is more powerful and stable than sensory imagination which can do so.

Furthermore, if learning is only familiarity with the agent intellect, there is no reason why anyone should learn one science rather than another.

Aristotle, moreover, said that the possible intellect is "the place of forms" (De anima, III, ch. 4, 492a 28); he goes on to say that a learned man "can exercise his function by himself" (ibid., 429b 8; cf. Physics , VIII, ch. 4, 255a); he also says that "for the mind phantasms are like sensible objects" (De anima, III, 431a 14; 432a 10), indicating that knowledge comes from sense data, not from a separate substance. Aristotle explains that habitual knowledge is a kind of act, intermediate between the pure potency of ignorance and the perfect act of actual thinking (ibid., 429b 6-10). Sense memory is a distinct power that stores singular images of the past, whereas the intellect performs the functions both of storing ideas abstract from time and of actually thinking about them.

2) If each individual has his own possible intellect, then the intelligible forms that it knows are individualized according to the number of people who have this knowledge. In that case these intelligible forms would be singular and not universal. ─ Just as a visual image in the retina is not what is seen, but that by which the colour of an object is seen, so ideas, or intelligible forms in the intellect, are not what is understood, but that by which the essences of things outside the mind are understood. These essences, as they exist materially, are singular and intelligible only in potency; in the intellect they are actually intelligible and universal regarding their objects, but singular with reference to their subject, which is the possible intellect, being multiplied by the number of intellects which they inform. Even if there were a single separated possible intellect, it would know things the same way, by singular intelligible species. Although these intelligible forms are that by which things are understood, they can, by reflection, become the object of thought, both by self-consciousness of one's particular thought and by universal consideration, as is done in the science of logic.

3) A teacher would be multiplying knowledge numerically according to the number of his students, not differently from the manner a material agent multiplies material forms. ─ The knowledge that a teacher imparts is the same for all as far as what is known is concerned, but is multiplied as the intelligible species and habit of knowledge are multiplied according to the number of his students. A teacher does not act like a natural agent, but as an artist imitating and utilizing nature; a person could learn by himself, but a teacher helps him to do so faster and better.

Also, just as material forms come from another natural agent and not from a separated substance, so the possible intellect should receive its forms from a power corresponding to it within the soul. In fact, the theory of a separated agent intellect hardly differs from the position of Plato, who said that our knowledge comes from separate subsistent ideas.

Besides, if the agent intellect were separate, it would have to act on us always or at least we would not be able to choose when to think or not to thing about anything.

The same hypothesis requires all men to to know the same things equally well, provided they all have the same phantasms.

One could object that the different action of the agent intellect could be explained by the different disposition of different people's cogitative sense, either─according to Ibn-Sînâ─disposing their possible intellect, or─according to Alexander of Aphrodisias and Ibn-Rushd,─disposing the phantasms so that they can become actually intelligible ─ As for the former, the possible intellect is always ready to receive and needs no disposition or intermediary; phantasms are not there to dispose the intellect, but they contain the object of intellection.

Besides, Ibn-Sînâ's position corresponds with his physics, which makes all natural agents mere dispositive causes of generation, with forms coming to matter from a separate agent intellect; in this case phantasms are really unnecessary, since the separate agent intellect can simply impress intelligible forms on the possible intellect. As for Alexander and Ibn-Rushd, their position also makes natural agents only dispose for the coming of a form from a separate agent.

Also, we have a desire and intention to understand, which indicates that we have the power to do so, just as any natural agent has within itself the principles of its action.

Besides, if man did not have this power, he could not be defined as rational, but rationality would be something supernatural to him.

Again, were all our ideas to come from a separate agent intellect, teaching would be impossible, since that would be somehow to do the work of the agent intellect.

Finally, if each man did not have his own agent intellect but were moved by an outside power, he would not be free or responsible for his actions, and there could be no moral science.

Since in every class of objects, just as in the whole of nature, there is something which is their matter, i.e., which is potentially all the individuals, and something else which is their cause or agent in that it makes them all (the two being related as an art to its material), these distinct elements must be present in the soul also. (De anima, III, 5, 430a 10-14)

Again, he goes on to say that the agent intellect is in the soul like a "habit" (ibid., 430a 15), as opposed to privation. He describes it as "separable, impassive and unmixed, by its essence being in act" (ibid., 430a 18); earlier he had said that the possible intellect is "separable" (429a 11, 429b 6), "unmixed with the body" (ch. 4, 429a 18,24), "impassive" (429a 15; 429b 24), although passive in a wide sense as receptive of intelligible species; so the word "separable" cannot be taken as referring to a separate substance, but to a power that "does not have an organ", as he said of the possible intellect. Then, after referring to knowledge in act as the formal identity of the mind in act with the intelligible in act, he says that "what is separated is only that which it is, and only this is immortal and everlasting" (430a 23); these words can only refer to the intellect in act which he was speaking about, which includes the possible and agent intellects, whereas the "passive intellect", which he says is corruptible (430a 24), must refer to the cogitative and other senses.

Moreover, the perfection of the soul comes from non-bodily activities, such as knowledge─which is the more perfect the more immaterial its object─and virtue, which keeps the soul from following bodily passions; such operation indicates the nature of its substance.

A sign of this is that man, in contrast to brutes, can understand the meaning of perpetual existence; so his natural desire to survive cannot be in vain.

Also, the act of understanding involves having intelligible ideas which are immaterial and universal. And it involves activity of the agent intellect which makes these ideas intelligible and incorruptible. So the intellective soul must be also incorruptible.

Besides, the soul has no contrary nor does it depend on the body for its existence. If the mind gets tired, this is not because of its own weakness, but only because of weakness of the imagination, memory and cogitative senses which it needs for the supply of data.

So we hear the rumination of the foolish: "The fate of man and the fate of animal is the same; as the one dies, so the other dies; both have the selfsame breath. Man is in no way better off than animal─since all is futile" (Sirach 3:19); "[Pharaoh and his soldiers] thought they would not be returned to us" (Qur'ân 22:39).

2) If there are many separated souls they would have to be different from one another formally, each in a different species; they could not change species by leaving the body; so even in this life each soul must be of a distinct species, and that is not plausible. ─ The difference among separated souls does not come from the form but from different relationships to a particular body, and this remains after death; otherwise the soul would be accidentally related to the body.

3) If the universe is eternal, then there would have to be an actually infinite number of separated souls, and that is impossible. ─ In reply to this objection, some simply said that human souls die with the body; others said that only one separated soul survives, common to all, such as the agent intellect (Ibn-Sînâ) or also the possible intellect (Ibn-Rushd); others (Plato) held for recycling of souls by reincarnation. Others (Ibn-Sînâ) said that there is no impossibility in an infinite number of separated souls, since they have no relationship to one another; thus this is an accidental infinitude. Aristotle did not express an opinion about this, but the last possibility matches his principles, since he only tried to disprove an actual infinitude in material substances (Physics, III, ch. 5, 205a; De caelo, ch. 5, 271b). The problem does not arise for those whose faith teaches that the universe had a beginning.

4) If the soul is not lost with the corruption of the body, then it must be united to it accidentally, and man is not a composite of body and soul. ─ A composite of matter and form is not accidental; the survival of the soul without the body proves nothing, because even prime matter survives, although under another form.

5) Every human operation depends on the body, either as an organ or, in the case of the intellect, as supplying data for knowledge, so that the mind cannot operate without phantasms; but if these are all corrupted at death, then the separated soul must remain unconscious, without any operation. ─ Operations that are without an organ do remain, such as understanding and willing, but their manner of operation is different. In the body, the soul cannot understand without phantasms or remember without the sense memory and imagination; but, separated form the body, it has existence all for itself without the body, and thus can understand by itself, like angelic substances; it can also receive knowledge from higher spirits.

A sign of this is that temperance helps people better to understand higher things; also in dreams or exstasy, when the exterior senses are quieted, people can receive knowledge from above that surpasses the human mode of understanding.

As for remembering, although sense memory goes at death, the intellect stores its knowledge indelibly. Sense emotions go, but the acts of the will remain, which can include joy, pleasure, the love of friendship etc.

Their lack of intelligence is shown because all animals of the same species do the same things, moved by nature and not by art; thus all sparrows make the same kind of nest and every species of spider makes the same kind of web.

A sign of this is the fact that no brute animal desires to exist perpetually, since all it knows is the particular here and now; they only act to preserve their species by generation.

Another sign is that the pleasures of brute animals all have to do with food or sex, so as to preserve themselves individually or as a species.

So we read: "The Lord looked at the earth and filled it with his good things. He covered its surface with every king of animal, and to it they will return" (Sirach 16:29-30); "You have a lesson in your herds: We let you drink from their stomachs and they are very useful for you; you eat their flesh and ride on them as on ships" (Qur'ân 23:21-22).

This counters the opinion of Plato, who held that the souls of brute animals are immortal (Phaedo, 23-25). His opinion might seem true because the soul's activity of moving the body is not an action of the body; thus he called the soul a "self-mover"; he also said that the soul moves the body in sensation. ─ As for sensation, this is not an action of the sense but a passion, as it receives the action of particular sensible objects, unlike the intellect, which receives in an immaterial and universal way.

Besides, different senses have different objects and use different organs; if sensation did not need a bodily organ the same sense power could receive any sensible object, since immaterial powers are not restricted in their objects.

Again, senses are corrupted by too intense an object, but not the intellect.

As for the soul moving itself, this cannot be, since only a body can be moved; moreover in any self-mover, one part has to be in act and the other in potency.

Even so, Plato used the term "self-motion" not for physical motion but for the operation of the soul. ─ But we have seen that sensation, and more so the passions of sense appetite, necessarily take place in a body. And a brute soul cannot move the body except through sensation and appetite. So a brute soul has no activity apart from the body; it therefore must die with the body.

2) The truth of intelligible realities is necessary and eternal; the same can therefore be said of the intellective soul. ─ Intelligible truths as objects exist eternally in the First Truth, but a created knowing subject need not exist eternally; the fact that this truth is the final cause of the intellect proves that the soul will live forever, but the capacity of God as efficient cause to create the soul does not prove that he created it from eternity.

3) Intellective souls are principal parts of the universe, and if every day more of them come into being, the universe must have been fundamentally imperfect. ─ The universe is perfect as long as the human race is present; its perfection consists in the species rather than in the individuals.

4) If God rested on the seventh day (Genesis 2:2; cf. Qur'ân 7:54 etc.), then he could not be constantly creating new souls. ─ God's rest can be understood as finishing the creation of different species in the world, not of the individuals of these species.

Another opposite position is that of Origen, who held that all souls were created at the beginning of the universe and then incarnated as babies are conceived. ─ Against this and the position that souls are eternal is the fact that in generation the form is always posterior in time.

Moreover, the whole man, body and soul, is more perfect than the soul alone, and in natural agency the perfect should come first.

More basically, any natural form must be united to its proper matter. Were the soul to pre-exist it would then have an accidental union with the body.

The soul would also suffer violence by being forced into this union against its will, or by being told to wait when it naturally desired it.

If it is said to be natural for a soul to jump in and out of a body from time to time, as the Platonists say, then the body would be totally accidental to it.

Again, if the will of the parents and of the separated soul must concur for a child to be conceived, then the birth will be by chance, since the parents do not consult the soul that is to come into their child's body.

Also, if souls were created before their bodies, their separate status would be better for them, since God makes things good, and he would not demote them to a lower state in order to lift a body to a higher state.

Further against Origen's position is the fact that the soul needs senses to gain knowledge, and that is the purpose of having a body; therefore it would have to be created with a body. The only alternative would be for all its knowledge to be infused into it beforehand, as the Platonists maintained, so that learning in this life would only be remembering; in that case the body would be an impediment to knowledge and the soul's union with it would be accidental and unnatural.

Also, it is clear that all everyone knows without learning is general principles, or being in general and its immediate consequences, such as the the principle that contradictories cannot both be true; even such knowledge comes from sense experience, such as of a particular whole to know that all wholes are greater than their parts.

Again, if souls pre-exist they must be infinite in number, since, even if the world did not always exist, nothing prevents it from lasting forever. Otherwise they must be finite and be re-used for different bodies; but that is also impossible, since were a soul to reincarnate it would have to be the same person that previously lived with that soul (as many people believe nowadays), since unity and being come from the form of a thing. Yet the individuality of the soul, like that of any form, comes from its relationship to a distinct matter or body to which is not only numerically distinct (by reason of division of extended quantity), but is also proportionate to a body of unique complexion and characteristics (fingerprints, DNA etc.), even in the case of identical twins.

Origen also said that souls were put into different bodies to punish them according to the gravity of their sins. ─ But something natural, such as the union of the soul with the body, cannot be a punishment, for that would mean that human nature is not good.

Besides, were the union of soul and body, which we say is a good, arise from the evil of punishment, it would be a chance result, and that is against divine wisdom.

Besides, we read God's words to Rebecca: "There are two nations in your womb... the elder will serve the younger" (Genesis 25:23), when neither had yet done anything either good or bad (cf. Romans 9:11); "God gives anyone (literally "any soul") responsibility only for what it can handle; to his credit will be what he merited and to his debit will be what he demerited" (Qur'ân 2:286). These and similar passages rule out merit or demerit in a pre-existence.

All these reasons make untenable the position that the the dead often return in their grandchildren, as is commonly believed in Africa. The resemblances of children to their ancestors can be explained by genetics and by their imitating the character and mannerisms of their parents; particular resemblances, such as scars or other marks, are coincidental.

One Qur'ânic passage seems to imply human pre-existence: "When your Lord took the descendants of the sons of Adam from their scrotums and made them testify on their part: 'Am I not your Lord?', they answered, 'Yes, we so testify'" (Qur'ân 7:172). ─ This passage is not talking about souls pre-existing without a body, but is based on Semitic biological ideas that the seed of the father is the total child and is merely planted in the womb of the mother; thus all the descendants of Adam would somehow be actually present in his seed. This passage and various adîth about Muammad's pre-existence became associated with the popular idea that everyone is created Muslim; it can be taken as a metaphorical and dramatic way of expressing that each person at conception is naturally subject to God (though, according to Christian theology of original sin, lacking a supernatural orientation to God).

On the origin of man's life we read: "Yahweh God shaped man from the soil of the ground and blew the breath of life into his nostrils, and man became a living being" (Genesis 2:7); "[God] who has created everything most excellently, began the creation of man from clay─then he made his descendance from an extraction of cheap liquid─then he shaped him and breathed into him from his spirit..." (Qur'ân 32:6-8). These passages imply the origin of man, soul with body, at the same time.

Likewise it has been seen that God cannot be the form of anything (I:27); nor can he be in potency to what is made out of his substance, or be subject to change, as this position implies.

Besides, the human soul continues to change according to knowledge and virtue, which cannot be true of God.

The human soul, moreover, has potencies and action distinct from its substance, which is not true of God.

Again, were the soul to be divine, all human souls would have to be one, since God is one.

The opinion that the soul is part of God could come from a materialist way of thinking, whereby God is the principle element or "force" of the universe, the nature of which the intellective soul shares. The idea also fits with those who make the soul a separated substance, the lowest in a hierarchy of cosmological divinities. Again, the very likeness of the human soul to God in intelligence could lead some to think it is of a divine nature, as also the verses quoted above (Genesis 2:7; Qur'ân 32:6-8). ─ But human intelligence falls way short of God's, and the phrases "breath of life" and "from his spirit" cannot be taken as if part of God's substance were cut off and put into man; they merely indicate an imperfect likeness of man's spirit to God's spirit.

Moreover, the soul is not identified with its existence; so its existence must come from God. Because matter is not part of it, it cannot come to be because the body comes to be, even though it shares its existence with the body. So it must be created by God from nothing.

Besides, since the human soul is simple, its coming into being is not the acquisition of a form, which is a principle of existence coming from a natural agent, but is only the acquisition of existence, which is the proper effect of the universal agent who is God.

Also, since the end of a thing corresponds to its origin, and the end of the human soul is to know and love God, and this transcends the whole created order, the origin of the soul must be God.

So, though the earth is said to produce plants and the waters various living creatures (Genesis 1:11,20) God is said directly to have created man (see texts at end of II:84).

2) Different agents cannot terminate in one effect; so if body and soul make a unit and the agent of the body is genetic action, then this action alone should produce the whole man. ─ The objection holds only with regard to uncoordinated agents; but in the making of a man genetic action serves as an instrumental dispositive cause, whereas God alone does the principal action of creating the rational soul.

3) Genetic action is the means by which new individuals of the same species are produced; that includes the form which makes it what it is, the human soul in the case of man. ─ Genetic action is only dispositive to the principal action which belongs to God alone.

4) If the origin of souls is pushed off to God, then he should be blamed for the conception of children by adultery. ─ God cooperates in the work of nature which generation is, not in the evil will of the parents.

5) If the genetic material, or body, exists before the soul, that would be as problematic as if the soul existed before the body. ─ It is normal for matter which is in potency to a form to precede the actual form; so that the ovum and the sperm of the parents is only potentially a child.

6) An action seems imperfect if it only produces part of a thing and not the whole, which would be the case if God created the soul, and genetic action the body. ─ The process is not imperfect if it is all the action of God, using genetic action as a dispositive instrument.

7) In any seed, such as of wheat or any other plant, the total plant is there, although it does not yet actually appear; the same should apply to the seed of man. ─ A seed or an embryo contains everything that does not exceed the corporeal nature of a thing; thus the human sperm and ovum cannot contain the intellective soul.

8) The end of the generative process should be the same as the middle and the beginning; but man starts from genetic material and gradually an embryo develops with different organs. ─ This smooth development does not show that the sperm and the ovum have a human soul, but merely that they are material disposed for the reception of this soul.

9) Bodies are made for souls and configured to serve their activities; thus Aristotle says that "the soul is the efficient cause of the body" (De anima, II, ch. 4, 415b 9); therefore, if the body is shaped by genetic material, it must include the soul. ─ Genetic material, namely, the sperm and the ovum, are living with a vegetative soul, but this does not constitute a species of its own, but is transient, operating under the principal agency of the parent to dispose for their union and reception of a rational soul.

10) If the soul does not exist before the body nor is already in the sperm, it seems that the body is first formed and then the soul infused; in this case the soul would seem to be made for the body, rather than vice versa. ─ Matter, which is for the completion of being of the form, precedes form in time, although it is posterior in the sense that the form which is the end of generation determines what disposition it ought to have for the form.

It should be noted here that Thomas Aquinas thought that at conception the embryo is first vegetative; then at a point it substantially changes into something with a sensitive soul; finally it substantially changes by having a rational soul infused. This theory was based on Aristotle's principle that the soul is "the act of an organic body" (De anima, II, ch. 1, 412a 29). He could not see that a new embryo had enough diversity of organs to support a rational soul from the start of conception. This view is overturned by modern microscopic knowledge of the organic complexity of a newly conceived embryo. Not only does science support the full humanity of the embryo right from the start, but this is a simpler explanation than Thomas' hypothesis of a series of substantial changes from a lower forms of life to higher ones.

Their existence (II:91): If human souls can subsist without their bodies, although this is not normal for them, we should expect there to be some separate substances which are naturally without bodies. The generic nature of an intelligent substance does not require being united with a body, although this is normally true for the species of intelligent substance which is the human soul.

Again, if we consider the scale of being, man occupies the highest place of material beings and the lowest of immaterial beings; so, for the completion of the order of creation, we should expect there to be higher spirits not united to bodies. These are more perfect because, being immaterial, they are totally and actually intelligible.

Likewise, it is fitting for there to be some intellects that directly know things that are actually intelligible, such as God and other spirits, since human knowledge is entirely restricted to knowing intelligible things through sensible things which are intelligible only in potency.

Thus we hear condemned the position of the Sadducees that "there is neither resurrection, nor angel nor spirit" (Acts 23:8); rather: "Piety is believing in God, the Last Day, the angels..." (Qur'ân 2:177).

Passages such as the following might give us the impression that spirits have bodies: "You created me [Iblîs, the angel who disobeyed] from fire, but you created him [Adam] from clay" (Qur'ân 38:86; see 55:15 for the jinn); "The angel of Yahweh appeared to Moses in a flame blazing from the middle of a bush" (Exodus 3:2). The flame in these cases is symbolic of the spiritual nature and the power of such creatures, but need not be taken as literally indicating the components of their nature.

In following Aristotle, Thomas only disagreed with his limiting the number of separate intelligent substances; Thomas held for the existence of other substances who are not employed in the movement of the heavenly bodies, since that job is not as essential to them as is the work of understanding. Thomas is of the opinion that the more noble a being is the more numerous it should be, so that the number of separated substances should exceed the number of species of material things in the world; these, unlike Plato's separate forms, are not of the same species as material things.

Besides, mental possibilities, such as mathematical sizes, numbers and division, far exceed the real possibilities of nature; therefore it is possible to have more species of intelligent substances than of material ones.

So we read: "A thousand thousand waited on him; ten thousand times ten thousand stood before him" (Daniel 7:10); "I am giving you a thousand angels to help you" (Qur'ân 8:90.

Moreover, the multiplication of separated substances by species adds more nobility to the universe than would the multiplication of individuals within a single species.

Moreover the ability of the human soul to give being to a body and the fact that it is only part of the human species makes it radically different from other intelligent substances.

Also, a separate intelligence has a completely different way of knowing than a human soul, for the soul knows from sensible images, whereas a separate substance does not.

Thus excluded is Origen's opinion that all spiritual substances were originally created equal; rather none are equal, but each one is naturally in a unique level of perfection.

Besides, since they are naturally superior to human souls, the object of their knowledge should be superior, namely, what is intelligible in itself, not just potentially intelligible like sensible things. So just as these substances are incorporeal, so should be the objects of their understanding, which excludes sensible things. Our intellect is moves from potency to act when sensible things are made actually intelligible; separated intellects should by nature always be in the act of knowing what is actually intelligible, and not sensible things that need to be made intelligible by the agent intellect.

Since place and time are characteristics of sensible things, it should also be clear that distance in place or time has no effect on the knowledge of separated substances. Their knowledge is of immaterial being which, being actually intelligible, is outside of place and time. Our own knowledge is characterized by time because it comes from sense images, but time does not apply to the essences that we know universally, since the quiddity of things is abstracted from sensible matter.

Besides, every living thing has some action going on all the time, such as metabolism for organic bodies; so some corresponding action should be always present in separated intellectual substances.

Again, to go in and out of action presupposes being moved at least accidentally, as our understanding is affected by the condition of our sensitive part; but separated substances are not subject to motion even accidentally.

A problem arises from the fact that none of these substances are of the same species, while knowledge implies having a likeness of the thing known. Since God created all of these substances directly, he knows them all directly as their proper cause, while these substances know God in as much as their being is a likeness of his.

Similarly, though the proper object of their knowledge is intelligible being, none of them know this comprehensively; so the higher angels have a wider knowledge through simpler concepts which are both more universal and more detailed about everything contained under these universals (contrary to universal knowledge in humans, which is imperfect until it is filled out with particular knowledge).

In any case, apart from their self-knowledge, these substances know through ideas or intelligible species, because it is impossible for the intelligible nature of another such substance directly to be the form of another intellect without being essentially identified with it as one being.

Besides, since these substances surpass the human intellect, they should also include in their knowledge what humans know, though in an intelligible, not a sensitive way.

Such substances know what is beneath them (lower separated substances or material things) without being degraded thereby, because the forms of lower things perfect their minds as intelligible species, and are not present in the mind as they are in their natural existence.

Besides, if the human soul knows singulars by two principles: sense and intellect, a separated substance, which is higher, should be able to know singulars by a single principle, the intellect.

Also, our knowledge comes by a process opposite to that of separated substances; we start from sensible singulars and abstract universals from their individuating conditions (hence we cannot know singulars by these universals), whereas separated substances have a knowledge that resembles divine creative knowledge, which extends not only to the form but also to the matter of a thing, which is the principle of its individuation.

Only God's intellect knows everything all at once, because he knows everything through one thing, his essence, and his action is his essence. Therefore there is no succession in his understanding, but his understanding is wholly and simultaneously perfect, enduring for ever and ever. AMEN.

NOTES