We know next to nothing about the condition of the Jews in Mohammedan Egypt in the ninth and tenth centuries. But the fact that the two first Jewish writers who busied themselves with philosophical problems came from Egypt would indicate that the general level of intellectual culture among the Jews at that time was not so low as the absence of literary monuments would lead us to believe. Every one knows of Saadia, the first Hebrew grammarian, the first Hebrew lexicographer, the first Bible translator and exegete, the first Jewish philosopher of mediÆval Jewry. He was born in Egypt and from there was called to the Gaonate of Sura in Babylonia. But not so well known is his earlier contemporary, Isaac ben Solomon Israeli, who also was born in Egypt and from there went later to Kairuan, where he was court physician to several of the Fatimide Califs. The dates of his birth and death are not known with certainty, but he is said to have lived to the age of one hundred years, and to have survived the third Fatimide Calif Al-Mansur, who died in 953. Accordingly we may assume the years of his birth and death as 855 and 955 respectively.

His fame rests on his work in theory and practice as a physician; and as such he is mentioned by the Arab annalists and historians of medicine.[26] To the Christian scholastics of mediÆval Europe he is known as the Jewish physician and philosopher next in importance to Maimonides.[27] This is due to the accident of his works having been translated into Latin by Constantinus Afer,[28] and thus made accessible to men like Albertus Magnus, Vincent of Beauvais, Thomas Aquinas and others. For his intrinsic merits as a philosopher, and particularly as a Jewish philosopher, do not by any means entitle him to be coupled with Maimonides. The latter, indeed, in a letter which he wrote to Samuel Ibn Tibbon, the translator of the "Guide of the Perplexed," expresses himself in terms little flattering concerning Israeli's worth as a philosopher.[29] He is a mere physician, Maimonides says, and his treatises on the Elements, and on Definitions consist of windy imaginings and empty talk. We need not be quite as severe in our judgment, but the fact remains that Israeli is little more than a compiler and, what is more to the purpose, he takes no attitude in his philosophical writings to Judaism as a theological doctrine or to the Bible as its source. The main problem, therefore, of Jewish philosophy is not touched upon in Israeli's works, and no wonder Maimonides had no use for them. For the purely scientific questions treated by Israeli could in Maimonides's day be studied to much better advantage in the works of the great Arabian Aristotelians, Al Farabi and Avicenna, compared to whom Israeli was mediocre. We are not to judge him, however, from Maimonides's point of view. In his own day and generation he was surpassed by none as a physician; and Saadia alone far outstrips him as a Jewish writer, and perhaps also David Al Mukammas, of whom we shall speak later. Whatever may be said of the intrinsic value of the content of his philosophical work, none can take away from him the merit of having been the first Jew, so far as we know, to devote himself to philosophical and scientific discussions, though not with the avowed aim of serving Judaism. The rest was bound to come later as a result of the impulse first given by him.

The two works of Israeli which come in consideration for our purpose are those mentioned by Maimonides in his letter to Samuel Ibn Tibbon spoken of above, namely, the "Book of the Elements,"[30] and the "Book of Definitions."[31] Like all scientific and philosophic works by Jews between the ninth and thirteenth centuries with few exceptions, these were written in Arabic. Unfortunately, with the exception of a fragment recently discovered of the "Book of Definitions," the originals are lost, and we owe our knowledge of their contents to Hebrew and Latin translations, which are extant and have been published.[32] We see from these that Israeli was a compiler from various sources, and that he had a special predilection for Galen and Hippocrates, with whose writings he shows great familiarity. He makes use besides of Aristotelian notions, and is influenced by the Neo-Platonic treatise, known as the "Liber de Causis," and derived from a work of Proclus. It is for this reason difficult to characterize his standpoint, but we shall not go far wrong if we call him a Neo-Platonist, for reasons which will appear in the sequel.

It would be useless for us here to reproduce the contents of Israeli's two treatises, which would be more appropriate for a history of mediÆval science. A brief rÉsumÉ will show the correctness of this view. In his "Book of the Elements" Israeli is primarily concerned with a definite physical problem, the definition of an element, and the number and character of the elements out of which the sublunar world is made. He begins with an Aristotelian definition of element, analyzes it into its parts and comes to the conclusion that the elements are the four well-known ones, fire, air, water, earth. Incidentally he seizes opportunities now and then, sometimes by force, to discuss points in logic, physics, physiology and psychology. Thus the composition of the human body, the various modes in which a thing may come into being, that the yellow and black galls and the phlegm are resident in the blood, the purpose of phlebotomy, the substantial character of prime form, that the soul is not an accident, the two kinds of blood in the body, the various kinds of "accident," the nature of a "property" and the manner in which it is caused—all these topics are discussed in the course of proof that the four elements are fire, air, water, earth, and not seed or the qualities of heat, cold, dryness and moisture. He then quotes the definitions of Galen and Hippocrates and insists that though the wording is different the meaning is the same as that of Aristotle, and hence they all agree about the identity of the elements. Here again he takes occasion to combat the atomic theory of the Mu?tazila and Democritus, and proves that a line is not composed of points. In the last part of the treatise he refutes contrary opinions concerning the number and identity of the elements, such as that there is only one element which is movable or immovable, finite or infinite, namely, the power of God, or species, or fire, or air, or water, or earth; or that the number is two, matter and God; or three, matter, form and motion; or six, viz., the four which he himself adopts, and composition and separation; or the number ten, which is the end and completion of number. In the course of this discussion he takes occasion to define pain and pleasure, the nature of species, the difference between element and principle. And thus the book draws to a close. Not very promising material this, it would seem, for the ideas of which we are in search.

The other book, that dealing with definitions of things, is more promising. For while there too we do not find any connected account of God, of the world and of man, Israeli's general attitude can be gathered from the manner in which he explains some important concepts. The book, as its title indicates, consists of a series of definitions or descriptions of certain terms and ideas made use of by philosophers in their construction of their scheme of the world—such ideas and terms as Intelligence, science, philosophy, soul, sphere, spirit, nature, and so on. From these we may glean some information of the school to which Israeli belongs. And in the "Book of the Elements," too, some of the episodic discussions are of value for our purpose.

Philosophy, Israeli tells us, is self-knowledge and keeping far from evil. When a man knows himself truly—his spiritual as well as his corporeal aspects—he knows everything. For in man are combined the corporeal and the spiritual. Spiritual is the soul and the reason, corporeal is the body with its three dimensions. In his qualities and attributes—"accidents" in the terminology of Israeli—we similarly find the spiritual as well as the corporeal. Humility, wisdom and other similar qualities borne by the soul are spiritual; complexion, stature, and so on are corporeal. Seeing that man thus forms an epitome, as it were, of the universe (for spiritual and corporeal substance and accident exhausts the classes of existence in the world), a knowledge of self means a knowledge of everything, and a man who knows all this is worthy of being called a philosopher.

But philosophy is more than knowledge; it involves also action. The formula which reveals the nature and aim of philosophy is to become like unto God as far as is possible for man. This means to imitate the activities of God in knowing the realities of things and doing what the truth requires. To know the realities of things one must study science so as to know the various causes and purposes existing in the world. The most important of these is the purpose of the union in man of body and soul. This is in order that man may know reality and truth, and distinguish between good and evil, so as to do what is true and just and upright, to sanctify and praise the Creator and to keep from impure deeds of the animal nature. A man who does this will receive reward from the Creator, which consists in cleaving to the upper soul, in receiving light from the light of knowledge, and the beauty of splendor and wisdom. When a man reaches this degree, he becomes spiritual by cleaving to the created light which comes directly from God, and praising the Creator. This is his paradise and his reward and perfection. Hence Plato said that philosophy is the strengthening and the help of death. He meant by this that philosophy helps to deaden all animal desires and pleasures. For by being thus delivered from them, a man will reach excellence and the higher splendor, and will enter the house of truth. But if he indulges his animal pleasures and desires and they become strengthened, he will become subject to agencies which will lead him astray from the duties he owes to God, from fear of him and from prayer at the prescribed time.

We look in vain in Israeli's two treatises for a discussion of the existence and nature of God. Concerning creation he tells us that when God wanted to show his wisdom and bring everything from potentiality to actuality, he created the world out of nothing, not after a model (this in opposition to Plato and Philo), nor for the purpose of deriving any benefit from it or to obviate harm, but solely on account of his goodness.

But how did the creation proceed? A fragment from the treatise of Israeli entitled "The Book of Spirit and Soul"[33] will give us in summary fashion an idea of the manner in which Israeli conceived of the order and connection of things in the world.

In the name of the ancients he gives the following account. God created a splendor. This having come to a standstill and real permanence, a spark of light proceeded from it, from which arose the power of the rational soul. This is less bright than the splendor of the Intelligence and is affected with shadow and darkness by reason of its greater distance from its origin, and the intervening Intelligence. The rational soul again becoming permanent and fixed, there issued from it likewise a spark, giving rise to the animal soul. This latter is endowed with a cogitative and imaginative faculty, but is not permanent in its existence, because of the two intervening natures between it and the pure light of God. From the animal soul there likewise issued a splendor, which produced the vegetative soul. This soul, being so far removed from the original light, and separated from it by the Intelligence and the other two souls, has its splendor dimmed and made coarse, and is endowed only with the motions of growth and nourishment, but is not capable of change of place. From the vegetative soul proceeds again a splendor, from which is made the sphere (the heaven). This becomes thickened and materialized so that it is accessible to the sight. Motion being the nature of the sphere, one part of it pushes the other, and from this motion results fire. From fire proceeds air; from air, water; from water, earth. And from these elements arise minerals, plants and animals.

Here we recognize the Neo-Platonic scheme of emanation as we saw it in Plotinus, a gradual and successive emanation of the lower from the higher in the manner of a ray of light radiating from a luminous body, the successive radiations diminishing in brightness and spirituality until when we reach the Sphere the process of obscuration has gone so far as to make the product material and visible to the physical sense. The Intelligence and the three Souls proceeding from it in order are clearly not individual but cosmic, just as in Plotinus. The relation between these cosmic hypostases, to use a Neo-Platonic term, and the rational and psychic faculties in man Israeli nowhere explains, but we must no doubt conceive of the latter as somehow contained in the former and temporarily individualized, returning again to their source after the dissolution of the body.

Let us follow Israeli further in his account of the nature of these substances. The Intelligence is that which proceeds immediately from the divine light without any immediate agency. It represents the permanent ideas and principles—species in Israeli's terminology—which are not subject to change or dissolution. The Intelligence contains them all in herself eternally and immediately, and requires no searching or reflection to reach them. When the Intelligence wishes to know anything she returns into herself and finds it there without requiring thought or reflection. We can illustrate this, he continues, in the case of a skilful artisan who, when he wishes to make anything, retires into himself and finds it there. There is a difference, however, in the two cases, because Intelligence always knows its ideas without thought or reflection, for it exists always and its ideas are not subject to change or addition or diminution; whereas in the smith a difficulty may arise, and then his soul is divided and he requires searching and thinking and discrimination before he can realize what he desires.

What has been said so far applies very well to the cosmic Intelligence, the ???? of the Neo-Platonists. It represents thought as embracing the highest and most fundamental principles of existence, upon which all mediate and discursive and inferential thinking depends. Its content corresponds to the Ideas of Plato. But the further account of the Intelligence must at least in a part of it refer to the individual human faculty of that name, though Israeli gives us no indication where the one stops and where the other begins.

He appeals to the authority of Aristotle for his division of Intelligence into three kinds. First, the Intelligence which is always actual. This is what has just been described. Second, the Intelligence which is in the soul potentially before it becomes actual, like the knowledge of the child which is at first potential, and when the child grows up and learns and acquires knowledge, becomes actual. Third, that which is described as the second Intelligence. It represents that state of the soul in which it receives things from the senses. The senses impress the forms of objects upon the imagination (fa?tas?a) which is in the front part of the head. The imagination, or phantasy, takes them to the rational soul. When the latter knows them, she becomes identical with them spiritually and not corporeally.

We have seen above the Aristotelian distinction between the active intellect and the passive. The account just given is evidently based upon it, though it modifies Aristotle's analysis, or rather it enlarges upon it. The first and second divisions in Israeli's account correspond to Aristotle's active and passive intellects respectively. The third class in Israeli represents the process of realization of the potential or passive intellect through the sense stimuli on the one hand and the influence of the active intellect on the other. Aristotle seems to have left this intermediate state between the potential and the eternally actual unnamed. We shall see, however, in our further study of this very difficult and complicated subject how the classification of the various intellects becomes more and more involved from Aristotle through Alexander and Themistius down to Averroes and Levi ben Gerson. It is sufficient for us to see here how Israeli combines Aristotelian psychology, as later Aristotelian logic and physics, with Neo-Platonic metaphysics and the theistic doctrine of creation. But more of this hereafter.

From the Intelligence, as we have seen, proceeds the rational soul. In his discussion of the general nature of the three-fold soul (rational, animal and vegetative) Israeli makes the unhistoric but thoroughly mediÆval attempt to reconcile Aristotle's definition of the soul, which we discussed above (p. xxxv), with that of Plato. The two conceptions are in reality diametrically opposed. Plato's is an anthropological dualism, Aristotle's, a monism. For Plato the soul is in its origin not of this world and not in essential unity with the body, which it controls as a sailor his boat. Aristotle conceives of the relation between soul and body as one of form and matter; and there is no union more perfect than that of these two constituent elements of all natural substances. Decomposition is impossible. A given form may disappear, but another form immediately takes its place. The combination of matter and form is the essential condition of sublunar existence, hence there can be no question of the soul entering or leaving the body, or of its activity apart from the body.

But Israeli does not seem to have grasped Aristotle's meaning, and ascribes to him the notion that the soul is a separate substance perfecting the natural body, which has life potentially, meaning by this that bodies have life potentially before the soul apprehends them; and when the soul does apprehend them, it makes them perfect and living actually. To be sure, he adds in the immediate sequel that he does not mean temporal before and after, for things are always just as they were created; and that his mode of expression is due to the impossibility of conveying spiritual ideas in corporeal terms in any other way. This merely signifies that the human body and its soul come into being simultaneously. But he still regards them as distinct substances forming only a passing combination. And with this pretended Aristotelian notion he seeks to harmonize that of Plato, which he understands to mean not that the soul enters the body, being clothed with it as with a garment, and then leaves it, but that the soul apprehends bodies by clothing them with its light and splendor, and thus makes them living and moving, as the sun clothes the world with its light and illuminates it so that sight can perceive it. The difference is that the light of the sun is corporeal, and sight perceives it in the air by which it is borne; whereas the light of the soul is spiritual, and intelligence alone can perceive it, not the physical sense.

Among the conceptual terms in the Aristotelian logic few play a more important part than those of substance and accident. Substance is that which does not reside in anything else but is its own subject. It is an independent existence and is the subject of accidents. The latter have no existence independent of the substance in which they inhere. Thus of the ten categories, in which Aristotle embraces all existing things, the first includes all substances, as for example, man, city, stone. The other nine come under the genus accident. Quantity, quality, relation, time, place, position, possession, action, passion—all these represent attributes which must have a substantial being to reside in. There is no length or breadth, or color, or before or after, or here or there, and so on except in a real object or thing. This then is the meaning of accident as a logical or ontological term, and in this signification it has nothing to do with the idea of chance. Clearly substance represents the higher category, and accident is inferior, because dependent and variable. Thus it becomes important to know in reference to any object of investigation what is its status in this respect, whether it is substance or accident.

The nature of the soul has been a puzzle to thinkers and philosophers from time immemorial. Some thought it was a material substance, some regarded it as spiritual. It was identified with the essence of number by the Pythagoreans. And there have not been wanting those who, arguing from its dependence upon body, said it was an accident and not a substance. Strange to say the Mutakallimun, defenders of religion and faith, held to this very opinion. But it is really no stranger than the maintenance of the soul's materiality equally defended by other religionists, like Tertullian for example, and the opposition to Maimonides's spiritualism on the part of Abraham ben David of PosquiÈres. The Mutakallimun were led to their idea by the atomic theory, which they found it politic to adopt as more amenable to theological treatment than Aristotle's Matter and Form. It followed then according to some of them that the fundamental unit was the material atom which is without quality, and any power or activity in any atom or group of atoms is a direct creation of God, which must be re-created every moment in order to exist. This is the nature of accident, and it makes more manifest the ever present activity of God in the world. Thus the "substantial" or "accidental" character of the soul is one that is touched on by most Jewish writers on the subject. And Israeli also refers to the matter incidentally in the "Book of the Elements."[34] Like the other Jewish philosophers he defends its substantiality.

The fact of its separability from the body, he says, is no proof of its being an accident. For it is not the separability of an accident from its substance that makes it an accident, but its destruction, when separated. Thus when a white substance turns green, the white color is not merely separated from its substance but ceases to exist. The soul is not destroyed when it leaves the body.

Another argument to prove the soul a substance is this. If the soul were an accident it should be possible for it to pass from the animal body to something else, as blackness is found in the Ethiopian's skin, in ebony wood and in pitch. But the soul exists only in living beings.

We find, besides, that the activity of the soul extends far beyond the body, and acts upon distant things without being destroyed. Hence it follows that the soul itself, the agent of the activity, keeps on existing without the body, and is a substance.

Having made clear the conception of soul generally and its relation to the body, he next proceeds to treat of the three kinds of soul. The highest of these is the rational soul, which is in the horizon of the Intelligence and arises from its shadow. It is in virtue of this soul that man is a rational being, discriminating, receptive of wisdom, distinguishing between good and evil, between things desirable and undesirable, approaching the meritorious and departing from wrong. For this he receives reward and punishment, because he knows what he is doing and that retribution follows upon his conduct.

Next to the rational soul is the animal soul, which arises from the shadow of the former. Being far removed from the light of Intelligence, the animal soul is dark and obscure. She has no knowledge or discrimination, but only a dim notion of truth, and judges by appearance only and not according to reality. Of its properties are sense perception, motion and change in place. For this reason the animals are fierce and violent, endeavoring to rule, but without clear knowledge and discrimination, like the lion who wants to rule over the other beasts, without having a clear consciousness of what he is doing. A proof that the animals have only dim notions of things is that a thirsty ass coming to the river will fly from his own shadow in the water, though he needs the latter for preserving his life, whereas he will not hesitate to approach a lion, who will devour him. Therefore the animals receive no reward or punishment (this in opposition to the Mutakallimun) because they do not know what to do so as to be rewarded, or what to avoid, in order not to be punished.

The vegetative soul proceeds from the shadow of the animal soul. She is still further removed from the light of Intelligence, and still more weighed down with shadow. She has no sense perception or motion. She is next to earth and is characterized by the powers of reproduction, growth, nutrition, and the production of buds and flowers, odors and tastes.

Next to the soul comes the Sphere (the heaven), which arises in the horizon and shadow of the vegetative soul. The Sphere is superior to corporeal substances, being itself not body, but the matter of body. Unlike the material elements, which suffer change and diminution through the things which arise out of them as well as through the return of the bodies of plants and animals back to them as their elements, the spiritual substances (and also the sphere) do not suffer any increase or diminution through the production of things out of them. For plants and animals are produced from the elements through a celestial power which God placed in nature effecting generation and decay in order that this world of genesis and dissolution should exist. But the splendor of the higher substances, viz., the three souls, suffers no change on account of the things coming from them because that which is produced by them issues from the shadow of their splendor and not from the essence of the splendor itself. And it is clear that the splendor of a thing in its essence is brighter than the splendor of its shadow, viz., that which comes from it. Hence the splendor of the vegetative soul is undoubtedly brighter than that of the sphere, which comes from its shadow. The latter becomes rigid and assumes a covering, thickness and corporeality so that it can be perceived by sight. But no other of the senses can perceive it because, although corporeal, it is near to the higher substances in form and nobility, and is moved by a perfect and complete motion, motion in a circle, which is more perfect than other motions and not subject to influence and change. Hence there is no increase or diminution in it, no beginning or end, and this on account of the simplicity, spirituality and permanence of that which moves it. The Intelligence pours of her splendor upon it, and of the light of her knowledge, and the sphere becomes intelligent and rational, and knows, without investigation or reflection, the lordship of its Creator, and that he should be praised and glorified without intermission. For this reason the Creator assigned to the Sphere a high degree from which it cannot be removed, and gave it charge of the production of time and the four seasons of the year, and the month and the day and the hour, and made it ruler of the production of perishable things in this world of generation and dissolution, so that the upper souls may find bodies to apprehend, to clothe with their light, and to make visible in them their activities according to the determination of God.

The Sphere by its motion produces the four elements, fire, air, water, earth; and the combinations of these in various proportions give rise to the minerals, plants and animals of this world, the highest of whom is man.

That the elements are those mentioned above and nothing else is proved by the definition of element and its distinction from "principle." A principle is something which, while being the cause of change, and even possibly at the basis of change, is not itself subject to change. Thus God is undoubtedly the cause of everything that happens in the world. He may therefore be called a principle of the world, but he does not enter with his essence the changing things. Hence it is absurd to speak of God as an element of the sublunar world. Matter, i. e., primary formless matter, does enter all changing things and is at the basis of all change; but it does not itself change. Hence matter also is a principle but not an element. An element is something which is itself a composite of matter and form, and changes its form to become something else in which, however, it is contained potentially, not actually. The product ultimately goes back to the element or elements from which it was made. When we follow this resolution of a given composite into its elements back as far as we can until we reach a first which is no longer produced out of anything in the same way as things were produced from it, we have the element. Such is the nature of fire, air, water, earth. All things are made from them in the manner above indicated. But there is nothing prior to them which changes its form to become fire, continues to reside potentially in fire and returns to its original state by the resolution of fire. The same applies to the other three.

The matter is now clear. The elements stand at the head of physical change and take part in it. Prior to the elements are indeed matter and form, but as logical principles, not as physical and independent entities. Hence it would seem, according to Israeli, that matter and form are side-tracked in the gradual evolution of the lower from the higher. For the elements, he tells us, come from the motion of the Sphere, the Sphere from the shadow of the Soul, the Soul from the shadow of the Intelligence, the Intelligence is created by God. To be sure he tells us that the Sphere is not body, but the matter of body. Yet the Sphere cannot take the place of prime matter surely, for it is undoubtedly endowed with form, nay is rational and intelligent, as we have seen.

When Israeli says that prior to the four elements there is nothing but the Omnipotence of God, he means that the sublunar process of change and becoming stops with the elements as its upper limit. What is above the elements belongs to the intelligible world; and the manner of their production one from the other is a spiritual one, emanation. The Sphere stands on the border line between the corporeal and the intelligible, itself a product of emanation, though producing the elements by its motion—a process apparently neither like emanation nor like sublunar becoming and change.

Creation in Israeli seems to be the same as emanation, for on the one hand he tells us that souls are created, that nothing precedes the four elements except the Omnipotence of God, and on the other that the elements come from the motion of the Sphere, and the souls issue from the shadow of the Intelligence. For matter and form there seems to be no room at all except as logical principles. This is evidently due to the fact that Israeli is unwittingly combining Aristotelian physics with Neo-Platonic emanationism. For Aristotle matter and form stand at the head of sublunar change and are ultimate. There is no derivation of matter or form from anything. The celestial world has a matter of its own, and is not the cause of the being of this one except as influencing its changes. God is the mover of the Spheres, but not their Creator, hence he stands outside of the world. This is Theism. In Israeli there is a continuity of God, the intelligible world and the corporeal, all being ultimately the same thing, though the processes in the two worlds are different. And yet he obviates Pantheism by declaring that God is a principle not an element.

We said before that Israeli takes no avowed attitude to Jewish dogma or the Bible. He never quotes any Jewish works, and there is nothing in his writings to indicate that he is a Jew and is making an effort to harmonize Judaism with philosophy and science. In words he refers to creation ex nihilo, which is not necessarily Jewish, it might be just as well Mohammedan or Christian. But in reality, as we have seen, his ideas of the cosmic process are far enough removed from the orthodox doctrine of creation as it appears in Bible and Talmud.

Incidentally we learn also something of Israeli's ideas of God's relation to mankind, of his commandments, and of prophecy. God created the world, he tells us, because of his goodness. He wanted to benefit his creatures. This could not be without their knowing the will of God and performing it. The will of God could not be revealed directly to everybody because the divine wisdom can speak only to those in whom the rational soul is mistress and is enlightened by the Intelligence. But people are not all of this kind; for some have the animal soul predominating in them, being on that account ignorant, confused, forward, bold, murderous, vengeful, unchaste like animals; others are mastered by the vegetative soul, i. e., the appetitive, and are thus stupid and dull, and given over to their appetites like plants. In others again their souls are variously combined, giving to their life and conduct a composite character. On this account it was necessary for God to select a person in whom the rational soul is separated, and illumined by the Intelligence—a man who is spiritual in his nature and eager to imitate the angels as far as it is possible for a man to do this. This man he made a messenger to mankind. He gave him his book which contains two kinds of teaching. One kind is spiritual in its nature, and needs no further commentary or interpretation. This is meant for the intellectual and discriminating. The other kind is corporeal, and requires spiritual interpretation. This is intended for the various grades of those who cannot understand directly the spiritual meaning, but who can grasp the corporeal teaching, by which they are gradually trained and prepared for the reception of higher truths. These people therefore need instructors and guides because a book alone is not sufficient for the purposes of those who cannot understand.

Dreams and prophecy are closely related, hence an explanation of the former will also throw light on the latter. A dream is caused by the influence of the Intelligence on the soul in sleep. The Intelligence receives its knowledge directly from God, and serves as a mediator between him and the soul, like a prophet who mediates between God and his creatures. In communicating to the soul the spiritual forms which it received from God, the Intelligence translates them into forms intermediate between corporeality and spirituality in order that they may be quickly impressed upon the common sense, which is the first to receive them. The common sense stands midway between the corporeal sense of sight and the imagination, which is in the anterior chamber of the brain, and is known as phantasy (Aristotelian fa?tas?a).

That the forms thus impressed on the common sense in sleep are intermediate between corporeal and spiritual is proved by the fact that they are different from the corporeal forms of things seen in the waking state. The latter are obscure and covered up, whereas those seen in sleep are finer, more spiritual and brighter. Proof of this is that a person sees himself in sleep endowed with wings and flying between heaven and earth. He sees the heavens opening and someone speaking to him out of the heaven, and so on. There would be no sense in all this if these phenomena had no spiritual meaning, for they are contrary to nature. But we know that they have real significance if interpreted by a really thoughtful person. The prophets also in wishing to separate themselves from mankind and impress the latter with their qualities, showed them spiritual forms of similar kind, which were preternatural. Hence all who believe in prophecy admit that dreams are a part of prophecy.

Now these intermediate forms which are impressed upon the common sense in sleep are turned over by it to the phantasy and by the latter to the memory. When the person awakes, he recovers the forms from the memory just as they were deposited there by the phantasy. He then consults his thinking power; and if this is spiritual and pure, the Intelligence endows him with its light and splendor and reveals to him the spiritual forms signified by the visions seen in sleep. He is then able to interpret the dream correctly. But if his powers of thought are not so good and are obscured by coverings, he cannot properly remove the husk from the kernel in the forms seen in sleep, is not able to penetrate to the true spirituality beneath, and his interpretation is erroneous.

This explanation does not really explain, but it is noteworthy as the first Jewish attempt to reduce prophecy to a psychological phenomenon, which was carried further by subsequent writers until it received its definitive form for the middle ages in Maimonides and Levi ben Gerson.

To sum up, Israeli is an eclectic. There is no system of Jewish philosophy to be found in his writings. He had no such ambitions. He combines Aristotelian logic, physics and psychology with Neo-Platonic metaphysics, and puts on the surface a veneer of theistic creationism. His merit is chiefly that of a pioneer in directing the attention of Jews to the science and philosophy of the Greeks, albeit in Arab dress. There is no trace yet of the Kalam in his writings except in his allusions to the atomic theory and the denial of reward and punishment of animals.