Knowledge must be of the real and the permanent. But the particular is not permanent, and the universal, which is permanent, is not real. Hence either there is no knowledge or there is a reality corresponding to the universal concept. This latter was the view adopted by Plato. Gersonides finds the reality in the thoughts of the Active Intellect, agreeing in this with the views of Philo and Augustine, subst.i.tuting only the Active Intellect for their Logos. Maimonides does not discuss the question, but it is clear from a casual statement that like Aristotle he does not believe in the independent reality of the universal (Guide III, 18).

In theoretical physics the Arabian Mutakallimun, we have seen (p. xxii), laid great stress on the theory of atom and accident as opposed to the concepts of matter and form by which Aristotle was led to believe in the eternity of the world. Accordingly every Mutakallim laid down his physical theory and based on it his proof of creation. This method was followed also by the early Jewish thinkers. The Karaites before Maimonides adopted the atomic theory without question. And Aaron ben Elijah, who had Maimonides's "Guide" before him, was nevertheless sufficiently loyal to his Karaite predecessors to discuss their views side by side with those of the Aristotelians and to defend them against the strictures of Maimonides. Saadia, the first Rabbanite philosopher, discusses no less than thirteen erroneous views concerning the origin and nature of the world, but he does not lay down any principles of theoretical physics explicitly. He does not seem to favor the atomic theory, but he devotes no special treatment to the subject, and in his arguments for creation as opposed to eternity he makes use of the Kalamistic concepts of substance and accident and composition and division. The same is true of Bahya Ibn Pakuda. Joseph Ibn Zaddik is the first who finds it necessary to give an independent treatment of the sciences before proceeding to construct his religious philosophy, and in so doing he expounds the concepts of matter and form, substance and accident, genesis and destruction, the four elements and their natures and so on--all these Aristotelian concepts. Ibn Daud follows in the path of Ibn Zaddik and discusses the relevant concepts of potentiality and actuality and the nature of motion and infinity, upon which his proof is based of the existence of G.o.d. Maimonides clears the ground first by a thorough criticism and refutation of the Kalamistic physics, but he does not think it necessary to expound the Aristotelian views which he adopts. He refers the reader to the original sources in the Physics and Metaphysics of Aristotle, and contents himself with giving a list of principles which he regards as established. Aristotle is now the master of all those who know. And he reigns supreme for over a century until the appearance of the "Or Adonai" of Hasdai Crescas, who ventured to deny some of the propositions upon which Maimonides based his proof of the existence of G.o.d--such, for example, as the impossibility of an infinite magnitude, the non-existence of an infinite fulness or vacuum outside of the limits of our world, the finiteness of our world and its unity, and so on.

These discussions of the fundamental principles of physics were applied ultimately to prove the existence of G.o.d. But there was a difference in the manner of the application. During the earlier period before the "Emunah Ramah" of Abraham Ibn Daud was written, the method employed was that of the Arabian Mutakallimun. That is, the principles of physics were used to prove the creation of the world in time, and from creation inference was made to the existence of a Creator, since nothing can create itself. The creation itself in time as opposed to eternity was proved from the fact of the composite character of the world.

Composition, it was said, implies the prior existence of the const.i.tuent elements, and the elements cannot be eternal, for an infinite past time is unthinkable. This method is common to Saadia, Bahya, Joseph Ibn Zaddik, and others.

With the appearance of Ibn Daud's masterpiece, which exhibits a more direct familiarity with the fundamental ideas of Aristotle, the method changed. The existence of G.o.d is proved directly from physics without the mediation of the doctrine of creation. Motion proves a mover, and to avoid an infinite regress we must posit an unmoved mover, that is, a first mover who is not himself moved at the same time. An unmoved mover cannot be corporeal, hence he is the spiritual being whom we call G.o.d.

Ibn Daud does not make use of creation to prove the existence of G.o.d, but neither does he posit eternal motion as Aristotle does. And the result is that he has no valid proof that this unmoved mover is a pure spirit not in any way related to body. This defect was made good by Maimonides. Let us frankly adopt tentatively, he says, the Aristotelian idea of the eternity of the world, _i. e._, the eternity of matter and motion. We can then prove the existence of an unmoved mover who is pure spirit, for none but a pure spirit can have an infinite force such as is manifested in the eternal motion of the world. Creation cannot be demonstrated with scientific rigor, hence it is not safe to build so important a structure as the existence of G.o.d upon an insecure foundation. Show that eternity of the world leads to G.o.d, and you are safe no matter what the ultimate truth turns out to be concerning the origin of the world. For if the world originated in time there is no doubt that G.o.d made it.

Thus Maimonides accepted provisionally the eternity of matter and motion, but provisionally only. No sooner did he prove his point, than he takes up the question of the world's origin and argues that while strict demonstration there is as yet none either for or against creation, the better reasons are on the side of creation.

Gersonides, on the other hand, was a truer Aristotelian than Maimonides and he decided in favor of the eternity of matter, though not of this our world.

The Jewish Mutakallimun, as we have seen, proved the existence of G.o.d from the fact that a created world implies a creator. The next step was to show that there is only one G.o.d, and that this one G.o.d is simple and not composite, and that he is incorporeal. The unity in the sense of uniqueness was shown by pointing out that dualism or pluralism is incompatible with omnipotence and perfection--attributes the possession of which by G.o.d was not considered to require proof. Maimonides, indeed, pointed out, in his opposition to the Mutakallimun, that if there is a plurality of worlds, a plurality of G.o.ds would not necessarily be in conflict with the omnipotence and perfection of each G.o.d in his own sphere (Guide I, 75), and he inferred the unity of G.o.d from his spirituality.

The simplicity of G.o.d was proved by arguing that if he is composite, his parts are prior to him, and he is neither the first, nor is he eternal, and hence not G.o.d; and the incorporeality followed from his simplicity, for all body is composite. Maimonides proved with one stroke G.o.d's existence, unity and incorporeality. For his argument from motion leads him to conceive of the first mover as a "separate" form or intellect.

This clearly denotes incorporeality, for body is composed of matter and form. But it also denotes unity, for the immaterial is not subject to numerical distinction unless the one be the cause and the other the effect. But in that case the cause alone is G.o.d.

Next in importance to the proof of G.o.d's existence, unity and incorporeality, is the doctrine of attributes. We have seen (p. xxiii) how much emphasis the Arabian Mutakallimun placed upon the problem of attributes. It was important to Jew, Christian and Mohammedan alike for a number of reasons. The crude anthropomorphism of many expressions in the Bible as well as the Koran offended the more sophisticated thinkers ever since Alexandrian days. Hence it was necessary to deal with this question, and the unanimous view was that the Biblical expressions in question are to be understood as figures of speech. The more difficult problem was how any predicates at all can be applied to G.o.d without endangering his unity. If G.o.d is the possessor of many qualities, even though they be purely spiritual, such as justice, wisdom, power, he is composite and not simple. The Christian theologians found indeed in this problem of attributes a philosophical support for the doctrine of the Trinity. Since G.o.d cannot be devoid of power, reason and life, he is trinitarian, though he is one. The difficulty was of course that the moment you admit distinctions within the G.o.dhead, there is no reason for stopping at three. And the Jewish critics were not slow to recognize this weakness in the system of their opponents. At the same time they found it necessary to take up a positive att.i.tude toward the question of attributes so as to harmonize the latter with G.o.d's absolute unity. And the essence of the solution of the problem was to explain away the attributes. Saadia says that the ascription of life, power and knowledge to G.o.d does not involve plurality in his essence. The distinction of three attributes is due to our limited mind and inadequate powers of expression. In reality the essence of which we predicate these attributes is one and simple. This solution did not seem thoroughgoing enough to Saadia's successors, and every one of the Jewish philosophers tried his hand at the problem. All agreed that the attributes cannot apply to G.o.d in the same signification as they have when we use them in our own experience. The meaning of the term attribute was investigated and the attributes were divided into cla.s.ses, until finally in the system of Maimonides this question too received its cla.s.sical solution. G.o.d is conceived as absolutely transcendent and unknowable. No positive predicate can apply to him so as to indicate his essence. We can say only what he is not, we cannot say what he is. There is not the faintest resemblance between him and his creatures. And yet he is the cause of the world and of all its happenings. Positive attributes signify only that G.o.d is the cause of the experiences denoted by the attributes in question. When we say G.o.d is just we mean that he is not unjust, and that he is the cause of all justice in the world.

Hence Maimonides says there are no essential attributes, meaning attributes expressive of G.o.d's essence, and the only predicates having application are negative and such as designate effects of G.o.d's causal activity in the world. Gersonides was opposed to Maimonides's radical agnosticism in respect of the nature of G.o.d, and defended a more human view. If G.o.d is pure thought, he is of the nature of our thought, though of course infinitely greater and perfect, but to deny any relation whatsoever between G.o.d's thought and ours, as Maimonides does, is absurd.

From G.o.d we pa.s.s to man. And the important part of man is his soul. It is proved that man has a soul, that the soul is not material or corporeal, that it is a substantial ent.i.ty and not a mere quality or accident of the body. Both Plato and Aristotle are laid under contribution in the various cla.s.sifications of the soul that are found in Saadia, in Joseph Ibn Zaddik, in Judah Halevi, in Abraham Ibn Daud, in Maimonides. The commonest is the three-fold division into vegetative, animal and rational. We also find the Platonic division into appet.i.tive, spirited and rational. Further psychological details and descriptions of the senses, external and internal, the latter embracing the common sense, memory, imagination and judgment, are ultimately based upon Aristotle and are found in Judah Halevi, Abraham Ibn Daud and Maimonides, who derived them from Avicenna and Alfarabi. In the Neo-Platonic writers, such as Isaac Israeli, Solomon Ibn Gabirol, Joseph Ibn Zaddik, Moses Ibn Ezra, Pseudo-Bahya, Abraham Bar Hiyya, and so on, we also find reference to the World Soul and its emanation from Intelligence. In the conception of the human soul the Jewish philosophers vary from the Platonic view, related to the Biblical, that the soul is a distinct ent.i.ty coming into the body from a spiritual world, and acting in the body by using the latter as its instrument, to the Aristotelian view that at least so far as the lower faculties of sense, memory and imagination are concerned, the soul is the form of the body, and disappears with the death of the latter. The human unit, according to this opinion, is body-and-mind, and the human activities are psycho-physical and not purely psychical as they are according to Plato. Some writers occupying intermediate positions combine unwittingly the Platonic and Aristotelian views, or rather they use Aristotelian expressions and interpret them Platonically (Saadia, Joseph Ibn Zaddik, Hillel ben Samuel).

As the influence of the Arab Aristotelians, Alfarabi, Avicenna and especially Averroes, began to make itself felt, the discussions about the Active Intellect and its relation to the higher Intelligences on the one hand and to the human intellect on the other found their way also among the Jews and had their effect on the conception of prophecy.

Aristotle's distinction of an active and a pa.s.sive intellect in man, and his ideas about the spheral spirits as pure Intelligences endowing the heavenly spheres with their motions, were combined by the Arabian Aristotelians with the Neo-Platonic theory of emanation. The result was that they adopted as Aristotelian the view that from G.o.d emanated in succession ten Intelligences and their spheres. Thus the first emanation was the first Intelligence. From this emanated the sphere of the fixed stars moved by it and the second Intelligence. From this emanated in turn the sphere of Saturn and the third Intelligence, and so on through the seven planets to the moon. From the Intelligence of the lunar sphere emanated the Active Intellect and the sublunar spheres of the four elements. These Intelligences were identified with the angels of Scripture. With some modifications this theory was adopted by the Jewish Aristotelians, Abraham Ibn Daud, Maimonides, Levi ben Gerson.

The Active Intellect was thus placed among the universal Intelligences whose function it is to control the motions of the sublunar world, and in particular to develop the human faculty of reason which is in the infant a mere capacity--a material intellect. Sensation and experience alone are not sufficient to develop the theoretical reason in man, for they present concrete, individual material objects, whereas the reason is concerned with universal truth. The conversion of sense experience into immaterial concepts is accomplished through the aid of the Active Intellect. And at the end of the process a new intellect is produced in man, the Acquired Intellect. This alone is the immortal part of man and theoretical study creates it. Averroes believed that this Acquired Intellect exists separately in every individual so long only as the individual is alive. As soon as the individual man dies, his acquired intellect loses its individuality (there being no material body to individuate it) and there is only one acquired intellect for the entire human species, which in turn is absorbed into the Active Intellect.

There is thus no individual immortality. Maimonides, it would seem, though he does not discuss the question in his "Guide," shared the same view. Gersonides devotes an entire book of his "Milhamot Adonai" to this problem, but he defends individuation of the acquired intellect as such and thus saves personal immortality.

The practical part of philosophy, ethics, the Mutakallimun among the Arabians discussed in connection with the justice of G.o.d. In opposition to the Jabariya and the Ashariya who advocated a fatalistic determinism denying man's ability to determine his own actions, some going so far as to say that right and wrong, good and evil, are entirely relative to G.o.d's will, the Mu?tazila insisted that man is free, that good and evil are absolute and that G.o.d is just because justice is inherently right, injustice inherently wrong. Hence reward and punishment would be unjust if man had not the freedom to will and to act. The Karaites Joseph Al Basir and Jeshua ben Judah discuss the problem of the nature of good and evil and vindicate their absolute character. G.o.d desires the good because it is good, and it is not true that a thing is good because G.o.d has commanded it. Freedom of man is a corollary of the goodness of G.o.d.

The Rabbanites take it for granted that good is good inherently, and G.o.d desires and commands it because it is identical with his wisdom and his will. Freedom of man does follow as a corollary from the justice of G.o.d and it is also taught in the Bible and the Talmud. The very fact of the existence of a divine law and commandments shows that man has freedom. And those pa.s.sages in Scripture which seem to suggest that G.o.d sometimes interferes with man's freedom are explained away by interpretations _ad hoc_. Our own consciousness of power to determine our acts also is a strong argument in favor of freedom. Nevertheless the subject is felt to have its difficulties and the arguments against free will taken from the causal sequences of natural events and the influence of heredity, environment and motive on the individual will are not ignored. Judah Halevi as well as Abraham Ibn Daud discuss these arguments in detail. But freedom comes out triumphant. It is even sought to reconcile the antinomy of freedom vs. G.o.d's foreknowledge. G.o.d knows beforehand from all eternity how a given man will act at a given moment, but his knowledge is merely a mirror of man's actual decision and not the determining cause thereof. This is Judah Halevi's view. Abraham Ibn Daud with better insight realizes that the contingent, which has no cause, and the free act, which is undetermined, are as such unpredictable. He therefore sacrifices G.o.d's knowledge of the contingent and the free so as to save man's freedom. It is no defect, he argues, not to be able to predict what is in the nature of the case unpredictable. Maimonides cannot admit any ignorance in G.o.d, and takes refuge in the transcendent character of G.o.d's knowledge. What is unpredictable for us is not necessarily so for G.o.d. As he is the cause of everything, he must know everything. Gersonides who, as we have seen, is unwilling to admit Maimonides's agnosticism and transcendentalism, solves the problem in the same way as Ibn Daud. G.o.d knows events in so far as they are determined, he does not know them in so far as they are contingent. There is still another possibility and that is that G.o.d knows in advance every man's acts because no act is absolutely free. And there is an advocate of this opinion also. Hasdai Crescas frankly adopts the determinist position on the basis of G.o.d's knowledge, which cannot be denied, as well as of reason and experience, which recognizes the determining character of temperament and motive. But reward and punishment are natural and necessary consequences, and are no more unjust than is the burning of the finger when put into the fire.

In respect to the details of ethical doctrine and the cla.s.sification of the virtues, we find at first the Platonic virtues and their relation to the parts of the soul, in Saadia, Pseudo-Bahya, Joseph Ibn Zaddik and even Abraham Ibn Daud. In combination with this Platonic basis expression is given also to the Aristotelian doctrine of the mean.

Maimonides, as in other things, so here also, adopts the Aristotelian views almost in their entirety, both in the definition of virtue, in the division of practical and intellectual virtues, and the list of the virtues and vices in connection with the doctrine of the mean. As is to be expected, the ultimate sanction of ethics is theistic and Biblical, and the ceremonial laws also are brought into relation with ethical motives. In this rationalization of the ceremonial prescriptions of Scripture Maimonides, as in other things, surpa.s.ses all his predecessors in his boldness, scientific method and completeness. He goes so far as to suggest that the inst.i.tution of sacrifice has no inherent value, but was in the nature of a concession to the crude notions of the people who, in agreement with their environment, imagined that G.o.d's favor is obtained by the slaughter of animals.

Among the peculiar phenomena of religion, and in particular of Judaism, the one that occupies a fundamental position is the revelation of G.o.d's will to man and his announcement of the future through prophetic visions. Dreams and divination had already been investigated by Aristotle and explained psychologically. The Arabs made use of this suggestion and endeavored to bring the phenomenon of prophecy under the same head. The Jewish philosophers, with the exception of Judah Halevi and Hasdai Crescas, followed suit. The suggestion that prophecy is a psychological phenomenon related to true dreams is found as early as Isaac Israeli. Judah Halevi mentions it with protest. Abraham Ibn Daud adopts it, and Maimonides gives it its final form in Jewish rationalistic philosophy. Levi ben Gerson discusses the finer details of the process, origin and nature of prophetic visions. In short the generally accepted view is that the Active Intellect is the chief agent in communicating true visions of future events to those worthy of the gift. And to become worthy a combination of innate and acquired powers is necessary together with the grace of G.o.d. The faculties chiefly concerned are reason and imagination. Moral excellence is also an indispensable prerequisite in aiding the development of the theoretical powers.

Proceeding to the more dogmatic elements of Judaism, Maimonides was the first to reduce the 613 commandments of Rabbinic Judaism to thirteen articles of faith. Hasdai Crescas criticised Maimonides's principle of selection as well as the list of dogmas, which he reduced to six. And Joseph Albo went still further and laid down three fundamental dogmas from which the rest are derived. They are the existence of G.o.d, revelation of the Torah and future reward and punishment.

The law of Moses is unanimously accepted as divinely revealed. And in opposition to the claims of Christianity and Mohammedanism an endeavor is made to prove by reason as well as the explicit statement of Scripture that a divine law once given is not subject to repeal. The laws are divided into two cla.s.ses, _rational_ and _traditional_; the former comprising those that the reason approves on purely rational and ethical grounds, while the latter consist of such ceremonial laws as without specific commandment would not be dictated by man's own reason.

And in many of these commandments no reason is a.s.signed. Nevertheless an endeavor is made to rationalize these also. Bahya introduced another distinction, viz., the "duties of the heart," as he calls them, in contradistinction to the "duties of the limbs." He lays stress on intention and motive as distinguished from the mere external observance of a duty or commandment.

Finally, some consideration is given in the works of the majority of the writers to eschatological matters, such as the destiny of the soul after death, the nature of future reward and punishment, the resurrection of the body and the Messianic period, and its relation to the other world.

This brief sketch will suffice as an introduction to the detailed treatment of the individual philosophers in the following chapters.

A HISTORY OF MEDIaeVAL JEWISH PHILOSOPHY

MEDIaeVAL JEWISH PHILOSOPHY

CHAPTER I

ISAAC ISRAELI

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 mediaeval 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 a.s.sume 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 mediaeval 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 ent.i.tle 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 att.i.tude 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 surpa.s.sed 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 mediaeval science. A brief _resume_ 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, a.n.a.lyzes 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 ident.i.ty 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 ident.i.ty of the elements, such as that there is only one element which is movable or immovable, finite or infinite, namely, the power of G.o.d, or species, or fire, or air, or water, or earth; or that the number is two, matter and G.o.d; 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 G.o.d, of the world and of man, Israeli's general att.i.tude can be gathered from the manner in which he explains some important concepts. The book, as its t.i.tle 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 cla.s.ses 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 G.o.d as far as is possible for man. This means to imitate the activities of G.o.d 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 G.o.d, 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 G.o.d, 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 G.o.d. Concerning creation he tells us that when G.o.d 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 ent.i.tled "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. G.o.d 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 G.o.d. 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 coa.r.s.e, 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 ill.u.s.trate 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 pa.s.sive. The account just given is evidently based upon it, though it modifies Aristotle's a.n.a.lysis, or rather it enlarges upon it. The first and second divisions in Israeli's account correspond to Aristotle's active and pa.s.sive intellects respectively. The third cla.s.s in Israeli represents the process of realization of the potential or pa.s.sive 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 cla.s.sification 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 mediaeval attempt to reconcile Aristotle's definition of the soul, which we discussed above (p. x.x.xv), 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 const.i.tuent 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 pa.s.sing 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.