This variation in expression is not accidental. It is deliberate and must be understood. Upon a careful examination we cannot fail to see that where the expression "Let there be" is used, the object so created exists in this world permanently and without change. Thus, "Let there be light" (Gen. i, 3). If in addition we have the corresponding expression, "And there was," in connection with the same object and followed by its name, it means that the object will continue its everlasting existence in the next world also. Hence, "And there was light" (_ib._). In the creation of the firmament and the luminaries we have the expression, "Let there be"; the corresponding expression at the end is in each case not, "And there was...," but, "And it was so." This signifies that in this world, as long as it lasts, the firmament and luminaries are permanent and without change; but they will have no continuance in the next world. In the creation of the sublunar world we do not find the phrase, "Let there be," at all, but such expressions as, "Let the waters be gathered together" (_ib._ 9), "Let the earth produce gra.s.s" (_ib._ 11), and so on. This means that these things change their forms and have no permanent existence in this world. The phrase, "And it was so,"

recording the realization of the divine command, signifies that they do not exist at all in the next world.

The case is different in man. We do not find the expression, "Let there be," in the command introducing his formation; hence he has no permanence in this world. But we do find the expression, "And the man became (lit. _was_) a living soul" (_ib._ 2, 7), which means that he will have permanent existence in the next world. The article before the word man in the verse just quoted indicates that not every man lives forever in the next world, but only the good. What manner of man he must be in order to have this privilege, _i. e._, of what nation he must be a member, we shall see later. This phase of the question the speculative thinkers cannot understand, hence they did not investigate it. Reason alone cannot decide this question; it needs the guidance of the Torah, which is divine.

Consulting the Torah on this problem, we notice that man is distinguished above other animals in the manner of his creation in three respects. (1) All other living beings were created by means of something else. The water or the earth was ordered to produce them. Man alone was made directly by G.o.d. (2) There are three expressions used for the creation of living things, "create" (Heb. bara), "form" (Heb. yazar), and "make" (Heb. ?asah). The water animals have only the first (_ib._ 1, 21), as being the lowest in the scale of animal life. Land animals have the second and the third, "formed" and "made" (_ib._ 1, 25; 2, 19). Man, who is superior to all the others, has all the three expressions (_ib._ 26, 27; 2, 7). (3) Man was given dominion over the other animals (_ib._ 1, 28).

As man is distinguished above the other animals, so is one nation distinguished above other men. In Isaiah (43, 7) we read: "Every one that is called by my name, and whom I have _created_ for my glory; I have _formed_ him; yea, I have _made_ him." The three terms, created, formed, made, signify that the reference is to man; and we learn from this verse that those men were created for his glory who are called by his name. But if we inquire in the Bible we find that the nation called by G.o.d's name is Israel, as we read (_ib._ 1), "Thus said the Lord that created thee, O Israel, Fear not; for I have redeemed thee, I have called thee by thy name; thou art mine," and in many other pa.s.sages besides. The reason for this is their belief in the unity of G.o.d and their reception of the Law. At the same time others who are not Israelites are not excluded from reaching the same degree through repentance.[157]

There is no system of ethics in Abraham bar Hiyya, and we shall in the sequel select some of his remarks bearing on ethics and pick out the ethical kernel from its homiletical and exegetical husk.

Man alone, he tells us, of all animal creation receives reward and punishment. The other animals have neither merit nor guilt. To be sure, their fortune in life depends upon the manner in which they respond to their environment, but this is not in the way of reward and punishment, but a natural consequence of their natural const.i.tution. With man it is different, and this is because of the responsible position man occupies, having been given the privilege and the ability to control all animal creation.[158]

The psychological basis of virtue in Abraham bar Hiyya is Platonic in origin, as it is in Pseudo-Bahya, though we do not find the four cardinal virtues and the derivation of justice from a harmonious combination of the other three as in the Republic of Plato, to which Pseudo-Bahya is ultimately indebted.

Man has three powers, we are told, which some call three souls. One is the power by which he grows and multiplies like the plants of the field.

The second is that by which he moves from place to place. These two powers he has in common with the animal. The third is that by which he distinguishes between good and evil, between truth and falsehood, between a thing and its opposite, and by which he acquires wisdom and knowledge. This is the soul which distinguishes him from the other animals. If this soul prevails over the lower two powers, the man is called meritorious and perfect. If on the other hand the latter prevail over the soul, the man is accounted like a beast, and is called wicked and an evil doer. G.o.d gives merit to the animal soul for the sake of the rational soul if the former is obedient to the latter; and on the other hand imputes guilt to the rational soul and punishes her for the guilt of the animal soul because she did not succeed in overcoming the latter.[159]

The question of the relative superiority of the naturally good who feels no temptation to do wrong, and the temperamental person who has to sustain a constant struggle with his pa.s.sions and desires in order to overcome them is decided by Abraham bar Hiyya in favor of the former on the ground that the latter is never free from evil thought, whereas the former is. And he quotes the Rabbis of the Talmud, according to whom the reward in the future world is not the same for the two types of men. He who must overcome temptation before he can subject his lower nature to his reason is rewarded in the next world in a manner bearing resemblance to the goods and pleasures of this world, and described as precious stones and tables of gold laden with good things to eat. On the other hand, the reward of the naturally perfect who is free from temptation is purely spiritual, and bears no earthly traces. These men are represented as "sitting under the Throne of Glory with their crowns on their heads and delighting in the splendor of the Shekinah."[160]

His theodicy offers nothing remarkable. He cites and opposes a solution frequently given in the middle ages of the problem of evil. This is based on the a.s.sumption that G.o.d cannot be the cause of evil. How then explain the presence of evil in the world? There is no a.n.a.lysis or cla.s.sification or definition of what is meant by evil. Apparently it is physical evil which Abraham bar Hiyya has in mind. Why do some people suffer who do not seem to deserve it? is the aspect of the problem which interests him. One solution that is offered, he tells us, is that evil is not anything positive or substantial. It is something negative, absence of the good, as blindness is absence of vision; deafness, absence of hearing; nakedness, absence of clothing. Hence it has no cause. G.o.d produces the positive forms which are good, and determines them to stay a definite length of time. When this time comes to an end, the forms disappear and their negatives take their place automatically without the necessity of any cause.

Abraham bar Hiyya is opposed to this solution of the problem, though he gives us no philosophic reason for it. His arguments are Biblical. G.o.d is the cause of evil as well as good, and this is the meaning of the word "judgment" (Heb. Mishpat) that occurs so often in the Bible in connection with G.o.d's attributes. The same idea is expressed in Jeremiah (9, 23) "I am the Lord which exercise loving kindness, judgment and righteousness in the earth." Loving kindness refers to the creation of the world, which was an act of pure grace on the part of G.o.d. It was not a necessity. His purpose was purely to do kindness to his creatures and to show them his wisdom and power. Righteousness refers to the kindness of G.o.d, his charity so to speak, which every one needs when he dies and wishes to be admitted to the next world. For the majority of men have more guilt than merit. Judgment denotes the good and evil distributed in the world according to the law of justice. Thus he rewards the righteous in the next world, and makes them suffer sometimes in this world in order to try them and to double their ultimate reward. He punishes the wicked in this world for their evil deeds, and sometimes he gives them wealth and prosperity that they may have no claim or defence in the next world. Thus evil in this world is not always the result of misconduct which it punishes; it may be inflicted as a trial, as in the case of Job. Abraham bar Hiyya's solution is therefore that there is no reason why G.o.d should not be the author of physical evil, since everything is done in accordance with the law of justice.[161]

CHAPTER IX

JOSEPH IBN ZADDIK

Little is known of the life of Joseph ben Jacob ibn Zaddik. He lived in Cordova; he was appointed _Dayyan_, or Judge of the Jewish community of that city in 1138; and he died in 1149. He is praised as a Talmudic scholar by his countryman Moses ibn Ezra, and as a poet by Abraham ibn Daud and Harizi, though we have no Talmudic composition from his pen, and but few poems, whether liturgical or otherwise.[162] His fame rests on his philosophical work, and it is this phase of his career in which we are interested here. "Olam Katon" or "Microcosm" is the Hebrew name of the philosophical treatise which he wrote in Arabic, but which we no longer possess in the original, being indebted for our knowledge of it to a Hebrew translation of unknown authorship.[163] Maimonides knew Joseph ibn Zaddik favorably, but he was not familiar with the "Microcosm." In a letter to Samuel Ibn Tibbon, the translator of his "Guide of the Perplexed," Maimonides tells us that though he has not seen the "Olam Katon" of Ibn Zaddik, he knows that its tendency is the same as that of the Brothers of Purity (_cf._ above, p. 60).[164] This signifies that its trend of thought is Neo-Platonic, which combines Aristotelian physics with Platonic and Plotinian metaphysics, ethics and psychology.

An examination of the book itself confirms Maimonides's judgment. In accordance with the trend of the times there is noticeable in Ibn Zaddik an increase of Aristotelian influence, though of a turbid kind; a decided decrease, if not a complete abandonment, of the ideas of the Kalam, and a strong saturation of Neo-Platonic doctrine and point of view. It was the fashion to set the Kalam over against the philosophers to the disadvantage of the former, as being deficient in logical knowledge and prejudiced by theological prepossessions. This is attested by the att.i.tude towards the Mutakallimun of Judah Halevi, Maimonides, Averroes. And Ibn Zaddik forms no exception to the rule. The circ.u.mstance that it was most likely from Karaite writings, which found their way into Spain, that Ibn Zaddik gained his knowledge of Kalamistic ideas, was not exactly calculated to prepossess him, a Rabbanite, in their favor. And thus while we see him in the manner of Saadia and Bahya follow the good old method, credited by Maimonides to the Mutakallimun, of starting his metaphysics with proofs of the world's creation, and basing the existence of G.o.d, his unity, incorporeality and other attributes on the creation of the world as a foundation, he turns into an uncompromising opponent of these much despised apologetes when he comes to discuss the nature of G.o.d's attributes, of the divine will, and of the nature of evil. And in all these cases the target of his attack seems to be their Karaite representative Joseph al-Basir, whose acquaintance we made before (p. 48 ff.).

He laid under contribution his predecessors and contemporaries, Saadia, Bahya, Pseudo-Bahya, Gabirol; and his sympathies clearly lay with the general point of view represented by the last, and his Mohammedan sources; though he was enough of an eclectic to refuse to follow Gabirol, or the Brethren of Purity and the other Neo-Platonic writings, in all the details of their doctrine; and there is evidence of an attempt on his part to tone down the extremes of Neo-Platonic tendency and create a kind of level in which Aristotelianism and Platonism meet by compromising. Thus he believes with Gabirol that all things corporeal as well as spiritual are composed of matter and form;[165] but when it comes to defining what the matter of spiritual things may be, he tells us that we may speak of the genus as the matter of the species--a doctrine which is not so Neo-Platonic after all. For we do not have to go beyond Aristotle to hear that in the definition of an object, which represents its _intelligible_ (opposed to sensible) essence, the genus is like the matter, the difference like the form. Of the universal and prime matter underlying all created things outside of G.o.d, of which Gabirol says that it is the immediate emanation of G.o.d's essence and const.i.tutes with universal form the Universal Intelligence, Ibn Zaddik knows nothing. Nor do we find any outspoken scheme of emanation, such as we see in Plotinus or with a slight modification in the cyclopdia of the Brethren of Purity, or as it is presupposed in the "Fons Vitae" of Gabirol. Ibn Zaddik does refer to the doctrine of the divine Will, which plays such an important role in the philosophy of Gabirol and of the Pseudo-Empedoclean writings, which are supposed to have been Gabirol's source.[166] But here, too, the negative side of Ibn Zaddik's doctrine is developed at length, while the positive side is barely alluded to in a hint. He takes pains to show the absurdity of the view that the divine will is a momentary ent.i.ty created from time to time to make possible the coming into being of the things and processes of our world--a view held by the Mutakallimun as represented by their spokesman al-Basir, but when it comes to explaining his own view of the nature of the divine will, and whether it is identical with G.o.d or not, he suddenly becomes reticent, refers us to the writings of Empedocles, and intimates that the matter is involved in mystery, and it is not safe to talk about it too plainly and openly. Evidently Ibn Zaddik was not ready to go all the length of Gabirol's emanationism and Neo-Platonic mysticism.

The Aristotelian ideas, of which there are many in the "Microcosm," are probably not derived from a study of Aristotle's works, but from secondary sources. This we may safely infer from the way in which he uses or interprets them. An Aristotelian definition is a highly technical proposition in which every word counts, and requires a definition in turn to be understood. In the Aristotelian context the reader sees the methodical derivation of the concept; and the several technical terms making up the definition are made clear by ill.u.s.trative examples. Aside from the context the proposition is obscure even in the original Greek. Now conceive an Arabic translation of an Aristotelian definition taken out of its context, and you do not wonder that it is misunderstood; particularly when the interpreter's point of view is taken from a school of thought at variance with that of Aristotle. This is exactly what happens to Ibn Zaddik. He quotes approvingly Aristotle's definition of the soul, and proceeds to interpret it in a manner not intended by the author of the "De Anima."[167] If he had read the context he could not have misunderstood the definition as he did.

Unlike his predecessors, Ibn Zaddik did not confine himself to a special topic in philosophy or to the metaphysical aspects of Judaism. Isaac Israeli and Gabirol discuss special questions in Physics and Metaphysics without bringing them into relation with Judaism or the text of the Bible. Saadia takes cognizance of philosophical doctrine solely with a view to establishing and rationalizing Jewish dogma, and only in so far as it may thus be utilized. Bahya and Abraham bar Hiyya confine their philosophical outlook within still narrower limits, having Jewish ethics as their primary concern. All of the latter make a feature of Biblical interpretation, which lends to their work the Jewish stamp and to their style the element of homeliness and variety. To this they owe in a measure their popularity, which, however, cannot be said for Abraham bar Hiyya, whose "Hegyon ha-Nefesh" was not printed until the second half of last century. The "Microcosm" of Ibn Zaddik is the first compendium of science, philosophy and theology in Jewish literature. And yet it is a small book; for Ibn Zaddik does not enter into lengthy discussions, nor does he adorn his style with rhetorical flourishes or copious quotations from Bible and Talmud. The "Olam Katon" is clearly meant for beginners, who require a summary and compendious view of so much of physics, psychology, metaphysics and ethics as will give them an idea of the position of man in the world, and his duties, theoretical and practical, in this life, that he may fulfil his destiny for which he was created.

It is very possible that Ibn Zaddik modelled his work on the Encyclopaedia of the Brethren of Purity, leaving out all that he regarded as unessential or objectional and abridging the rest.

Accordingly, the "Microcosm" is divided into four parts. The first part treats of what is called in the Aristotelian cla.s.sification of the sciences Physics, _i. e._, the principles and const.i.tution of the corporeal world and its processes. The second treats of man, including anthropology and psychology. The third is devoted to a discussion of the existence, unity, incorporeality and other attributes of G.o.d, based upon the doctrine of the creation of the world. This bears the stamp of the Kalam, and is indebted to the writings of Saadia, Bahya and Joseph al-Basir. It covers the topics usually treated by the Mutakallimun in the division of their works, known by the name of "Bab al Tauhid,"

treatise on Unity. The fourth part corresponds to the "Bab al Adi" of the Kalam, _i. e._, the second division of Kalamistic works devoted to theodicy, or vindication of G.o.d's justice in his dealings with mankind.

Hence it includes theological questions of an ethical nature, like freedom of the will, reasons for divine worship, the nature of reward and punishment, and so on.

The book was written, Ibn Zaddik tells us, in answer to the question of a pupil concerning the meaning of such terms as "perfection" and "permanent good," used by philosophers. They are not of this world these men say, and yet every man of intelligence should seek them. This is a very difficult subject, made more so by the small number of persons engaged in its study. Particularly in our own generation is this true, that the value of knowledge and investigation is not recognized. People are Jews in name only, and men only in outward appearance. Former ages were much superior in this regard.

Two fundamental requisites are necessary for the knowledge of our subject. They are the knowledge of G.o.d, and performance of his will. For this purpose we must understand the works of the philosophers. But these in turn require a knowledge of the preliminary sciences of arithmetic, geometry, music, astronomy, and logic. This takes a long time and is likely to weary the student, especially the beginner. I have therefore made it my purpose to show how a man can know himself, for from a knowledge of self he will come to a knowledge of all. Man is called "Microcosm," a world in miniature, because he has in him represented all the elements of the universe. His body resembles the corporeal world; his rational soul the spiritual world. Hence the importance of knowing himself, and hence the definition of philosophy as a man's _knowledge of himself_. Philosophy is the science of sciences and the end thereof, because it is the path to a knowledge of the Creator.[168]

Here we see at the outset Ibn Zaddik's Neo-Platonic tendency to make a short cut to knowledge through the study of man instead of the painful and laborious mastery of the preliminary sciences. And so it was that the Neo-Platonists added little to Aristotle's study of nature, concentrating their attention upon the intelligible or spiritual world.

The first thing we must do then is to show that the human body is similar to the corporeal world. This will require an a.n.a.lysis of the structure of the latter. But before examining the _objects_ of knowledge, we must say a word about the process of knowing. Man perceives things in two ways--through sense and through intellect. His senses give him the accidents of things, the sh.e.l.l or husk, so to speak.

He perceives color through sight, sound through hearing, odor through smell, and so on. It takes reason to penetrate to the essence of an object. Take as an example a book. The sense of sight perceives its color, and through the color its form. This is then apprehended by the power of imagination or representation. The latter in turn hands it over to the cogitative power of the rational soul, from the reflection of which results the spiritual reality of the object, which is its knowledge. So we see that the reason knows the essence and reality of a thing, whereas the senses know only its husk and its accidents. This same thing is stated by the philosopher in another form. The senses, he says, know only the particular, the universal can be known by the intellect only. This is because the soul is fine and penetrating, while the body is gross, and can reach the surface only.

We may also cla.s.sify knowledge from another point of view as necessary (or immediate), and demonstrated (or mediate). Necessary knowledge is that which no sane man can deny. Such knowledge may be of the senses, as the sight of the sun or the sound of thunder; or it may be of the reason, such as that the whole is greater than its parts. We may then enumerate four kinds of things known directly without the help of other knowledge, (1) The percepts of the senses. (2) Truths generally admitted by reason of their self-evidence. (3) Traditional truths, _i. e._, truths handed down by a reliable and wise man, or by a community worthy of credence. (4) First principles or axioms. These four can be easily reduced to two; for traditional truths ultimately go back to the testimony of the senses; while first principles or axioms are included in self-evident propositions. We thus have two kinds of necessary or immediate knowledge, the data of sense, and self-evident propositions.

The latter kind is superior to the former, because man shares sense knowledge with the lower animals; whereas rational propositions are peculiar to him alone.

Demonstrated knowledge is built upon necessary knowledge, and is derived from it by means of logical inference.[169]

We may now proceed to discuss the principles of the corporeal world.

Matter is the foundation and principle of a thing. All things, natural as well as artificial, are composed of matter and form. Wood is the common matter of chair and bed. Their forms are different. So the common matter of the four elements is the prime matter endowed with the form of corporeality, _i. e._, with the capacity of filling place. This form of corporeality makes the prime matter corporeal substance. Matter is relative to form, form is relative to matter.

Spiritual things also have matter and form. In corporeal artificial things like ring or bracelet, the matter is gold, the form is the form of ring or bracelet, the efficient cause is the art of the goldsmith, the final cause or purpose is the adornment. In spiritual things we may compare genus to matter, species to form, specific difference to efficient cause, the individual to the final cause.

Everything exists either by itself (_per se_) or in something else.

Matter exists by itself, form exists in something else, in matter.

Matter is potentially substance; after it a.s.sumes a form it becomes actual substance. In reality there is no matter without form, but in thought we can remove the form and leave the matter.

Substance may be described as that which bears opposite and changing qualities. No substance can be the opposite of another substance through its substantiality, but through its accidents; for opposition resides in quality. Matter receiving form is substance. Absolute substance is simple and spiritual, for it cannot be perceived through the five senses. When the philosophers say that all body is substance, and that the individual is a substance, they use substance in contradistinction to accident, meaning that the individual exists by itself, and needs not another for its existence, unlike accidents, which must have something to exist in.

This absolute substance, which is simple and spiritual, seems to be identical with Gabirol's "substantia quae sustinet decem praedicamenta,"

the substance which supports the ten categories. Gabirol means by it that which remains of a corporeal substance when we take away from it everything that qualifies it as being here or there, of a particular nature or size, in a given relation, and so on.

The expression corporeal world includes the celestial spheres and all which is under them. To be sure, the body of the sphere is different from the other bodies in matter and form and qualities. It consists of a fifth nature, different from the four elements. It is not cold, or it would move downward like earth and water. It is not warm, or it would move upward like air and fire. It is not wet, for it would then roll like the waves of the sea. Nor is it dry, for it would condense and not move at all. Not being any one of these qualities, which const.i.tute our four elements, the sphere is not a composite of them either; for the simple is prior to the composite, and we cannot regard the elements of the sublunar world as prior and superior to the spheres.

The sphere is neither light nor heavy. For light and heavy are relative terms. An object is heavy when out of its natural place, light when in its natural place. Thus a stone is heavy when it is away from the earth, which is its natural place, but is light when it comes to rest where it belongs. The sphere is never out of its place or in its place, as it moves constantly in a circle. Hence it is neither light nor heavy.

Ibn Zaddik's definition of light and heavy as being relative, and dependent on the relation of the object to its natural place is peculiar, and would lead him to say that fire and air are also heavy when out of their natural place, which is outside of, and above earth and water. But this does not seem in consonance with the Aristotelian use of these terms. According to Aristotle an object is heavy if its tendency is to move to the centre of the world; it is light if it moves away from the centre to the circ.u.mference. Hence earth and water are heavy, fire and air are light. The natural place of a body or element is that to which it has a tendency to move, or in which it has a tendency to rest, when left to itself. Hence a body will always move to its natural place when away from it and under no restriction; and its heaviness or lightness does not change with its position.

To continue, the sphere moves in a circle, the most perfect of all motions, having neither beginning nor end. It is more perfect than all bodies, and the knowledge of G.o.d is not hidden from it as it is hidden from us. Whatever moves in a circle must move around a body at rest; for if it moves around another moving body, this second body must have another body around which it moves, and this third body another, and so on _ad infinitum_, which is impossible. Hence the sphere moves around a body at rest. This is the earth.

The four elements of the sublunar world are, fire, air, water, earth. In their purity these elements have neither color nor taste, nor odor nor any other sensible property. For the elements are simple bodies, whereas the sensible qualities are the result of the composition of the elements. If air had color, we should see it as we see all colored things; and all other things would appear to us in the color of air, as is the case when we look through a colored gla.s.s. The same argument applies to water.

The elements change into each other. We see water changing under the effect of heat into vapor, and the vapor condenses again under the influence of cold and changes back to water, namely, rain. Air changes into fire when flint strikes iron. Fire cannot exist here unless it has something to take hold of; otherwise it changes into air. Earth and water change into each other very slowly, because earth is hard to change.

The basis of the four elements is a substance filling place as a result of its a.s.suming the form of corporeality, _i. e._, extension in three directions. Filling place, it moves; moving, it becomes warm. When its motion is completed, it necessarily comes to rest and becomes cold. Heat and cold are the active powers, wet and dry are the pa.s.sive qualities, wet being a.s.sociated with heat, dry with cold. The mixture of these qualities with the corporeal basis results in the four elements.

The three natures, mineral, plant, animal are composed of the four elements. When a seed is put in the ground it cannot grow without water, and sunshine and air. These form its food, and food is a.s.similated to the thing fed. Our bodies are composed of the four elements, because they are nourished by plants. The general process of the sublunar world is that of genesis and dissolution. The genesis of one thing is the dissolution of another. The dissolution of the egg is the genesis of the chicken; the dissolution of the chicken is the genesis of the four elements; for in the living being the elements are potential, and they become actual when the animal dies. This continuous process of genesis and dissolution proves that this world is not permanent, for the basis of its processes is change.[170]

The human body corresponds to the corporeal world, and is similar to it in its nature and matter. Man's body is subject to genesis and decay like other objects. It is composed of the elements and returns to them.

It has in it the nature of minerals, plants and animals. It has the power of growth, sustenance and reproduction like plants. Man is like animal in having motion and sensation. He has the spirited power and the appet.i.tive like other animals. His body is perfect because it has resemblances to all kinds of plants and animals. His body as a whole resembles great trees, his hair is like gra.s.s and shrubs. Animals have various qualities according to the relation of the animal soul to the body. Thus the lion has strength, the lamb meekness, the fox shrewdness, and so on. Mankind includes all of these qualities. In the same way various animals have various instincts resembling arts, such as the weaving of the spider, the building of the bird and the bee, and so on.

They also subsist on various foods. Man alone combines all arts and all kinds of food.

The human body has three dimensions like inanimate bodies. It is also similar to the bodies of plants and animals, and at the same time is distinguished alone among animals by its erect position. This is due to the fact that man's nature is proportionate, and his body is purer and finer than other bodies. Thus we see when oil is pure, its flame rises in a straight line; when the oil is impure the flame is not straight.

Another thing proving that man's nature is superior to that of other animals is that the latter live in that element which is akin to their const.i.tution--fish in water, birds in air, quadrupeds on land. Man alone can inhabit all three. Another reason for man's erect position is that he is a plant originating in heaven. Hence his head, which is the root, faces heaven.[171]

Man has three souls, a plant soul, an animal soul and a rational soul.

He must have a plant soul to account for the fact that man grows like other plants and dies like them. For if he can grow without a plant soul, plants can do the same. And if this too is granted, then there is no reason why mountains and stones should not grow also. Again, if man can grow without a plant soul, he can live without an animal soul, and know without a rational soul, which is absurd.