Source: Introduction to The Spiritual Physic of Rhazes, trans. Arthur J. Arberry (London: John Murray, 1950).
Rhazes, “undoubtedly the greatest physician of the Islamic world and one of the great physicians of all time”,1 was born at Raiy, near modern Teheran, in 864, and died there in 925. As is the case with many of the most famous Arab scholars and writers, comparatively little authentic is known of the details of his life; for the Arabs of old were curiously incurious about the private affairs of their great men of learning, it being sufficient for them to know that they had composed valuable books and carried forward the frontiers of science and letters. Rhazes (this is the latinized form of his name, which was in full Abū Bakr Muhammad ibn Zakarīyā al-Rāzī) is said to have come to the study of medicine somewhat late in life; according to most authorities, he devoted his earlier years to alchemy, mathematics, philosophy and literature. One biographer relates that “in his youth, he played on the lute and cultivated vocal music, but, on reaching the age of manhood, he renounced these occupations, saying that music proceeding from between mustachoes and a beard had no charms to recommend it”.2
Whenever it was that he turned his mind to more serious things—a respectable authority puts this event in the thirties of Rhazes’ life3 —certainly Baghdad was the city where he learned his medicine. By this time, the capital of the Abbasid Empire had firmly established itself as the leading centre of learning in the known world. Successive rulers, from al-Mansūr (754–75) and Hārūn al-Rashīd (d. 809) to al-Ma’mūn (813–33), had liberally endowed institutes for the study of the ancient Greek sciences; the writings of Plato, Aristotle, Plotinus, Hippocrates, Galen, Euclid, Oribasius, Paul of Aegina and many other philosophers, mathematicians and physicians were translated into Arabic, chiefly by the Christian Hunain ibn Ishāq (809–77) and his school. The family of Bukht-Yishū‘, likewise Christians, enjoyed the confidence of their Muslim masters because of their supreme skill in medicine and surgery. When Rhazes came to Baghdad he would have found there fully-equipped hospitals, well-stocked libraries, and a sound tradition of teaching and research. It is said that he studied there under a pupil of the great Hunain who was acquainted with Greek, Persian and Indian medicine1 ; some give the name of ‘Alī ibn Rabban al-Tabarī as his teacher, the author of a celebrated book entitled The Paradise of Wisdom,2 but this is impossible because al-Tabarī was dead before Rhazes came to Baghdad.
Rhazes presently returned to his birthplace in order to enter the service of the local ruler, and having already achieved a wide reputation as a physician he was given charge of the new hospital there. Later he went back to Baghdad, and directed a great hospital in the capital.3 Thereafter he is stated to have travelled extensively and enjoyed the patronage of a number of royal masters. He composed a very great number of books, especially on medicine; his most celebrated works being the Kitāb al-Mansūrī, dedicated to and named after Abū Sālih al-Mansūr ibn Ishāq ibn Ahmad ibn Nūh, prince of Kirman and Khurasan,1 the Kitāb al-Mulūkī, written in honour of ‘Alī ibn Wēh-Sūdhān of Tabaristan, and the Hāwī, a gigantic encyclopaedia which was unfinished at Rhazes’ death and was edited by his pupils, it is said at the instance of Ibn al-‘Amīd (d. 970), the vizier of the Buyid ruler Rukn al-Daula, who recovered the notebooks containing the rough draft from Rhazes’ sister.2
Many anecdotes are related to illustrate Rhazes’ pre-eminence as a physician. Of these, one is chosen for reproduction here; not that one can have absolute confidence in its authenticity—for its chronology raises difficulties—but nevertheless it gives an attractive and probably accurate picture of the character of the great sage, and of his royal patrons.
Another of the House of Sāmān, Amīr Mansūr b. Nūh b. Nasr, became afflicted with an ailment which grew chronic, and remained established, and the physicians were unable to cure it. So the Amīr Mansūr sent messengers to summon Muhammad b. Zakariyyā of Ray to treat him. Muhammad b. Zakariyyā came as far as the Oxus, but when he saw it he said: “I will not embark in the boat; God Most High saith, Do not cast yourselves into peril with your own hands; and, again, it is surely a thing remote from wisdom voluntarily to place one’s self in so hazardous a position.” Ere the Amīr’s messenger had gone to Bukhara and returned, he had composed a treatise entitled Mansūrī. So when a notable arrived with a special led-horse, bringing a message intermingled with promises of reward, he handed this Mansūrī to him, saying: “I am this book, and by this book thou canst attain thine object, so that there is no need of me.”
When the book reached the Amīr he was in grievous suffering wherefore he sent a thousand dinars and one of his own private horses, saying: “Strive to move him by all these kind attentions, but, if they prove fruitless, bind his hands and feet, place him in the boat, and fetch him across.” So, just as the Amīr had commanded, they urgently entreated Muhammad b. Zakariyyā, but to no purpose. Then they bound his hands and feet, placed him in the boat, and, when they had ferried him across the river, released him. Then they brought the led-horse, fully caparisoned, before him, and he mounted in the best of humours, and set out for Bukhara. And when they enquired of him, saying, “We feared to bring thee across the water lest thou shouldst cherish enmity against us, but thou didst not so, nor do we see thee vexed in heart,” he replied: “I know that every year several thousand persons cross the Oxus without being drowned, and that I too should probably not be drowned; still, it was possible that I might perish, and if this had happened they would have continued till the Resurrection to say, A foolish fellow was Muhammad b. Zakariyyā, in that, of his own free will, he embarked in a boat and so was drowned. But when they bound me, I escaped all danger of censure; for then they would say, They bound the poor fellow’s hands and feet, so that he was drowned. Thus should I have been excused, not blamed, in case of my being drowned.”
When they reached Bukhara, he saw the Amīr and began to treat him, exerting his powers to the utmost, but without relief to the patient. One day he came in before the Amīr and said: “To-morrow I am going to try another method of treatment, but for the carrying out of it you will have to sacrifice such-and-such a horse and such-and-such a mule,” the two being both animals of note, so that in one night they had gone forty parasangs.
So next day he took the Amīr to the hot bath of Jū-yi-Mūliyān, outside the palace, leaving that horse and mule ready equipped and tightly girt in the charge of his own servant; while of the King’s retinue and attendants he suffered not one to enter the bath. Then he brought the King into the middle of the hot bath, and poured over him warm water, after which he prepared a draught and gave it to him to drink. And he kept him there till such time as the humours in his joints were matured.
Then he himself went out and put on his clothes, and, taking a knife in his hand, came in, and stood for a while reviling the King saying: “Thou didst order me to be bound and cast into the boat, and didst conspire against my life. If I do not destroy thee as a punishment for this, I am not Muhammad b. Zakariyyā.”
The Amīr was furious, sprang from his place, and, partly from anger, partly from fear of the knife and dread of death, rose to his feet. When Muhammad b. Zakariyyā saw the Amīr on his feet he turned round and went out from the bath, and he and his servant mounted, the one the horse, the other the mule, and turned their faces towards the Oxus. At the time of the second prayer they crossed the river, and halted nowhere till they reached Merv. When Muhammad b. Zakariyyā reached Merv, he alighted, and wrote a letter to the Amīr, saying: “May the life of the King be prolonged in health of body and effective command! According to agreement this servant treated his master, doing all that was possible. There was, however, an extreme weakness in the natural caloric, and the treatment of the disease by ordinary means would have been a protracted affair. I therefore abandoned it, and carried you to the hot bath for psychical treatment, and administered a draught, and left you so long as to bring about a maturity of the humours. Then I angered the King, so that an increase in the natural caloric was produced, and it gained strength until those humours, already softened, were dissolved. But henceforth it is not expedient that a meeting should take place between myself and the King.”
Now after the Amīr had risen to his feet and Muhammad b. Zakariyyā had gone out, the Amīr sat down and at once fainted. When he came to himself he went forth from the bath and called to his servants, saying, “Where has the physician gone?” They answered, “He came out from the bath, and mounted the horse, while his attendant mounted the mule, and went off.”
Then the Amīr knew what object he had in view. So he came forth on his own feet from the hot bath; and tidings of this ran through the city, and his servants and retainers and people rejoiced greatly, and gave alms, and offered sacrifices, and held high festival. But they could not find the physician, seek him as they might. And on the seventh day Muhammad b. Zakariyyā’s servant arrived, riding the horse and leading the mule, and presented the letter. The Amīr read it, and was astonished, and excused him, and sent him a horse, and a robe of honour, and equipment, and a cloak, and arms, and a turban, and a male slave, and a handmaiden; and further commanded that there should be assigned to him in Ray from the settled estates a yearly allowance of two thousand dinars and two hundred ass-loads of corn. These marks of honour he forwarded to him by the hand of a trusty messenger, together with his apologies. So the Amīr completely regained his health, and Muhammad b. Zakariyyā attained his object.1
It would be attractive to conjecture that the Spiritual Physick, which was certainly composed for the same ruler as the Mansūrī, was written as a result of this encounter, to explain in greater detail the scientific principles underlying the psychological treatment which Rhazes had adopted with such complete success.
All our sources agree that in his later years Rhazes was smitten by cataract, and became quite blind. When he was urged to submit to cupping, he is said to have replied, “No, I have seen the world so long that I am tired of it.”2 Confirmatory evidence of his failing sight is furnished by Rhazes’ autobiography, to which reference will presently be made. The spirit in which he faced death is illustrated by some verses he is reported to have composed in his old age.3
Rhazes is described as a man with a “great, scaly head”, generous and gracious in his dealings with others, and most compassionate towards the poor, whom he treated free of charge and even maintained out of his own purse. His lectures were thronged by students, and arranged in such a fashion that several junior and senior lecturers dealt with any inquiries which they were competent to answer, only referring to him matters which passed their range of knowledge.1
The foregoing is the sum of what we are told about Rhazes by Arab and Persian biographers, apart from monumental lists of the titles of his books. A fortunate chance has preserved for us a little tract in which he set about in his later days to justify the manner of life he had lived, and the direction of his studies; and from these pages we are able to reconstruct a far clearer image of the man than anything these unsatisfying sources can supply.2
Rhazes’ medical writings were highly prized in the Middle Ages, alike by Muslims, Jews and Christians, and were accepted as the basis for modern research. His Hāwī was translated into Latin under the title Continens by the Sicilian Jew Faraj ibn Sālim (Farragut) in 1279; the gigantic version was printed in its entirety five times between 1488 and 1542. The Kitāb al-Mansūrī (“Liber Almansoris”, the companion of the present work) and Kitāb al-Mulūkī (“Liber Regius”) were also published in Latin and cherished by medieval physicians as among their most precious works of reference. His monograph On Smallpox and Measles was printed in various translations some forty times between 1498 and 1866, and has been praised by modern doctors for its clinical accuracy.1 With the possible exception of Avicenna and Averroes, whose influence was in any case philosophical rather than scientific, no man so powerfully affected the course of learning in the Middle Ages and the early Renaissance as Rhazes. It is scarcely surprising that Chaucer’s Doctor of Physic should have included him in his impressive list of authorities.
His philosophical writings were never so widely known, chiefly because they were condemned as heretical by almost all Muslim opinion. Even the illustrious Abū Raihān al-Bīrūnī, the historian of India and broad-minded investigator of Indian philosophy and religion, added his voice to the general chorus of disapproval. Though he wrote a catalogue of Rhazes’ works extant in his day, amounting to 184 items, and confessed that in his youth he was carried away by his enthusiasm for study to the point of reading Rhazes’ Metaphysica, he roundly condemned him for dabbling in freethought, and even spoke of his blindness as a Divine retribution.1 Ibn Hazm, who composed a massive work on sects and heresies, singled out Rhazes for particular rejection.2 So much for the orthodox; even the Ismailis, renegades that they were, disowned his philosophical teaching, and Nāsir-i Khusrau the poet3 and Hamīd al-Dīn al-Kirmānī the theologian4 applied themselves energetically to refuting him. Orthodox and unorthodox were alike shocked most of all by Rhazes’ book On Prophecy—which, needless to say, has not survived—in which he seems to have maintained the thesis that reason is superior to inspiration, a view naturally intolerable to any devout Muslim.
The Spiritual Physick, which is here offered in the first translation to be made into any language, belongs rather to the realm of popular ethics than to that of high philosophy; yet it enables us to obtain a clear view of the background of Rhazes’ thought, and even to glimpse those dangerous propositions which brought down on his head the execrations of the faithful. The book is preserved in several manuscripts, and was first studied in modern times by the Dutch orientalist De Boer.5 The editio princeps was published in 1939 by the late Paul Kraus,6 a most able and promising scholar, a victim of Nazi persecution, who committed suicide at Cairo during the recent war. His premature death was a severe blow to learning: the present translation is put out as a small tribute to his memory.
Rhazes, as the list of his writings suggests, and the Spiritual Physick and Autobiography (among other works) amply prove, was thoroughly at home with the books of the Greek philosophers and physicians. He wrote for instance a commentary on Plato’s Timaeus,1 an epitome of Aristotle’s writings on logic,2 a refutation of Porphyry,3 and epitomes of Hippocrates’ Aphorisms4 and of the medical works of Galen and Plutarch.5 He was familiar besides with Oribasius, Aetius and Paul of Aegina, and was unquestionably well grounded in the entire canon of Greek works translated by Hunain ibn Ishāq and his school. His studies of Arabic literature are attested not only by the admirable fluency and eloquence with which he uses the language, but also by the apt poetical quotations which flavour his discourse; the present book contains an anecdote which proves his familiarity with the mentality and technical vocabulary of the Arab grammarians. He writes like a master, and his style has the unmistakable ring of a man confident in the supremacy of his own reason and erudition. His spirit of rational inquiry is entirely Greek; his Persian blood is proved by his fondness for anecdote, besides innumerable little nuances of thought and expression. His attitude of tolerant agnosticism anticipates the more celebrated outlook of another Persian scientist who in modern times has achieved universal fame and popularity—Omar Khayyám.
In the Autobiography Rhazes rejects the “early life” of Socrates—the inaccurate legend that he refused all pleasures, eschewed all human intercourse, and lived in a barrel in the wilderness—but approves of his “later life” when he is said to have married, begat children, and even taken up arms against the enemy. In that essay, as in the Spiritual Physick, he revolts against the unreasonable austerities of monks and anchorites, and takes the view that God is far too compassionate to impose upon human beings burdens heavier than they can bear. Regarding the immortality of the soul he appears to reserve judgment, though he quotes freely Plato’s opinion and outlines the psychological analysis of the Timaeus. His theory of pleasure—that it consists of a return to the state of nature—is based on the Philebus. When he writes on the fear of death, we seem to catch many echoes of the Epicurean teaching which Lucretius immortalized in a famous passage of the De Natura Rerum. Rhazes’ general attitude might be summed up as one of intellectual hedonism; though its origins in classical philosophy are obvious, it reflects very characteristically the outlook of the cultured Persian gentleman, constantly down the ages informing Iranian thought and life.
The Spiritual Physick appears therefore as the product of a curiously perfect blend of two civilizations, expressed in the language of a third; an admirable synthesis of science and metaphysics, shaped in the mind of a master physician and given verbal form by a master of language. It is scarcely an exaggeration to say that the book is unique in Arabic literature. The author hardly betrays himself as a Muslim, though his name Muhammad proves him so to have been; otherwise he would have done as all other Arabs did who wrote on ethics, elaborating his discourse with quotations from the Koran and the sayings of the Prophet, and only introducing the views of Greek thinkers where they appeared to accord with sound Islamic teaching. Avicenna was much more orthodox; he even wrote commentaries on parts of the Koran.
Rhazes’ God is a very rational and reasonable God, a God, we might almost say, with a sense of humour, an eminently Persian God. When we lay down this book, we feel that we have been in the presence of a man who knew no vain fear because he had analysed fear out of his mind; a man who knew no vain hope because he knew that the laws of nature were as beneficent as they were immutable; a man indifferent to fame and wealth because he was intellectually persuaded of their worthlessness; a man whose counsel is a sure guide through the baffling perplexities that are the inevitable accompaniment of human life, a sage and reasonable comfort under the dark shadows of extreme affliction and death.
To conclude these prefatory remarks, we here append some passages drawn from Rhazes’ defence of the philosophic life, so that we may leave the reader with the voice of the author himself speaking. He begins the Autobiography by stating the charge that unnamed critics had brought against him.
Certain men of a speculative turn, discriminating and of undoubted attainments, having observed that we consort with our fellows and engage in various manners of earning a livelihood, reproach us on this account, finding it to be detrimental in us and asserting that we are swerving aside from the philosophic life.
The criticism is particularly levelled at his alleged failure to live up to the ideals of Socrates, his confessed master, who is pictured as living a life of utmost rigour; at the same time Socrates himself is criticized—according to this legend—for conduct contrary to the laws of nature and liable to lead to the extinction of the human race and the desolation of the world. Rhazes agrees with the objection that is raised to Socrates’ “earlier life”, but makes it clear that he differs from his master “only quantitively, not qualitatively”; he is in full agreement with the view that life should be lived in a disciplined manner, but cannot accept the doctrine of extreme self-abnegation. He argues the proposition that pleasure is not to be indulged when it is irrational in its appeal, much along the same lines as in the Spiritual Physick. Then he turns to the problem of pain.
Since we have laid it down as the foundation of our case that our Lord and Ruler is kindly and compassionate towards us and regards us with loving care, it follows from this that He hates that any pain should befall us; it also follows that whatever happens to us not of our own earning and choosing but due to some necessity of nature, is to be regarded as inevitable. It therefore behoves us not to pain any sentient creature whatsoever, unless it deserves to be pained, or unless it be to avert from it still greater pain.
Rhazes follows up the implications of this conclusion by condemning blood sports except when practised against carnivorous beasts such as lions, tigers and wolves; at the same time he urges the annihilation of snakes, scorpions and other noisome creatures that have no discoverable beneficial use or property. From the animal kingdom he turns back to man.
Since it is prohibited by the verdict of reason and justice alike for any man to inflict pain upon another, it follows from this that he should not inflict pain upon himself either. Many things come under this general observation as being rejected by the arbitrament of reason—for instance, the Indian way of propitiating God by burning the body and casting it down upon sharp spikes, or the Manichean practice of self-mutilation to overcome the sexual urge, excessive fasting, and defiling oneself by washing in urine. The same heading also includes—though at a much lower level—the monasticism and hermit-life taken up by some Christians, and the fashion followed by many Muslims of spending their whole time at mosque, declining to earn their living, and contenting themselves with little and unappetizing food and rough, uncomfortable clothes.
The practice of austerity is obviously easier for those not accustomed to luxury from birth than for the children of rich parents; the latter cannot be required to compete with the former in this respect on a basis of equality.
But the boundary which cannot be transgressed is that they should refrain from such pleasures as may not be attained save by perpetrating cruelty and murder—in short, all those things that provoke the wrath of God and are forbidden by the verdict of reason and justice.
This is what Rhazes calls the “upper limit” of discipline which he holds to be obligatory for all men to respect; to keep above the “lower limit” is equally important.
This means that a man should eat such food as will not harm him or make him ill, while not exceeding this to partake of such delicious and appetising dishes as are desired for the mere gratification of pleasure and greed, and not to allay hunger; that he should wear such clothes as his skin can tolerate without discomfort, not hankering after fine and flowery raiment; and that he should seek such a dwelling-place as may shelter him from excessive heat and cold, not going beyond this to look for magnificent residences painted up in fine colours and lavishly ornamented; unless indeed he possesses such ample means that he can afford to maintain this style without injustice or aggression towards others and without exerting himself unduly to earn the wherewithal.
Such are the two extremes within which it behoves the philosopher to confine himself.
Since the Creator is Omniscient and All-Just, since He is absolute knowledge and justice and mercy, and since He is our Creator and Ruler and we are His creatures and subjects; whereas that servant is most beloved by his master who the most closely follows his master’s lead and example, it follows that the creature nearest to God’s favour is he who is the most knowing, the justest, the most merciful and compassionate. This indeed is what the philosophers meant when they said that the purpose of philosophy was “to make oneself like to God, to the greatest extent possible to man.”1 That is the sum total of the philosophic life.
Rhazes refers his readers to the Spiritual Physick for a detailed explanation of his argument; then he concludes his defence as follows.
Now that we have explained what we desired to set forth in this place, we will go back to set out what we have to say in reply to our critics; declaring that by God’s help and assistance we have up to this very day in no way conducted ourselves in a manner meriting our expulsion from the title of philosopher. For only those men deserve to have their names expunged from the roll of philosophy who have fallen short in both branches of philosophy—the theoretical and the practical—together, either through ignorance of what a philosopher should know, or out of failure to conduct their lives as a philosopher ought. We, God be praised and thanked for His assistance and guidance, are innocent of such failure.
To take theory: if we possessed only so much strength of knowledge as was necessary to compose this present book, that alone would suffice to prevent our name from being expunged from the roll of philosophy; not to mention our other writings [Rhazes here adds a considerable list of titles] which amount in all to approximately two hundred items, reckoning in books, pamphlets and essays, down to the time of making this present pamphlet; writings which cover all branches of philosophy, physical and metaphysical alike. As for mathematics, I freely concede that I have only looked into this subject to the extent that was absolutely indispensable, not wasting my time upon refinements; of set purpose, not out of incapacity for the study. If any man wishes to have my excuse on this head, I make bold to assert that the right course is in fact that which I have followed, not the one adopted by some so-called philosophers who fritter away their whole lives indulging in geometrical superfluities. If therefore the amount of knowledge I possess is not sufficient for me to deserve the name of philosopher, I should very much like to know who of my contemporaries is so qualified.
Now as to the practical side: by God’s help and succour I have never in all my life transgressed the twain limits which I have defined, nor have I committed any act so far as I am aware that would justify my conduct being called unphilosophical. I have never kept the ruler’s company in the way of bearing arms or undertaking the control of affairs; my service has been confined to that of a physician and a courtier charged with two responsibilities—to treat and restore him when he was sick, and when he was well to win his confidence and offer him counsel; and in counselling him, let God be my witness, I have only advised such actions as I hoped would prove beneficial both to him and to his subjects. I have never been observed to be greedy to amass wealth, or to be extravagant in spending it; I have not been forward to quarrel and dispute with my fellows, or to oppress them—on the contrary, it is well known that I have always acted in the very opposite manner, to the point of sacrificing many of my own rights for the sake of others.
As for my habits of eating and drinking, and my amusements, those who have observed me frequently will be aware that I have never been guilty of excess or extravagance in these, any more than in regard to my clothes, my mount, my servants and handmaidens.
My love and passion for knowledge, and my labours to acquire the same, are familiar to all who have kept my company or seen me at my studies; from my youth up to this very time, I have not ceased to devote myself to this object. If ever I have come upon a book I have not read, or heard tell of a man I have not met, I have not turned aside to any engagement whatever—even though it has been to my great loss—before mastering that book or learning all that man knew. So great in fact have been my endeavours and endurance, that in a single year I have written as many as 20,000 pages in a script as minute as that used for amulets. I was engaged fifteen years upon my great compendium, working night and day, until my sight began to fail and the nerves of my hand were paralysed, so that at the present time I am prevented from reading and writing; even so I do not give up these occupations so far as I am able, but always enlist the help of someone to read and write for me.
If the amount of my accomplishments in all these matters is still regarded by my critics as disqualifying me from occupying the rank of a philosopher in practice, and if their conception of the purpose of following the philosophic life is other than what we have described, let them state their charge against us, either verbally or in writing. Then, if they can prove superior knowledge, we will accept their verdict; on the other hand, if we can establish any error or weakness in their case, we will refute it. Or let me be lenient with them; let me acknowledge that I have been wanting on the practical side; yet what have they to say on the side of theory? If they find me deficient in this respect too, they only have to state their case and we will examine it; if they are right, we will submit, and if they are wrong, we will reject their charge. But if they do not hold me inadequate on the theoretical side, the best they can do is to profit of my theory, and pay no heed to my personal conduct, remembering what the poet has said:
[1 ]M. Meyerhof in Legacy of Islam, p. 323.
[2 ]Ibn Khallikān, Biographical Dictionary (transl. De Slane), III, p. 312.
[3 ]Ibn Abī Usaibi‘a, I, p. 309. Ibn Khallikān, loc. cit., says “over forty”.
[1 ]Legacy of Islam, p. 323.
[2 ]Ibn Khallikān, loc. cit.
[3 ]According to the authority quoted by Ibn Abī Usaibi‘a, this was the great hospital established by the Buyid ruler ‘Adud al-Daula; but Ibn Abī Usaibi‘a rightly remarks that Rhazes lived long before ‘Adud al-Daula, and indeed the hospital named after the latter was not completed until 978, see Encylopaedia of Islam, I, p. 143.
[1 ]Ibn Khallikān, III, p. 313; Encycl. of Islam, III, p. 256. The tradition that the book was dedicated to the Samanid ruler Abū Sālih al-Mansūr ibn Nūh involves an anachronism, for that prince did not come to the throne until 961, long after Rhazes’ death.
[2 ]Ibn Abī Usaibi‘a, I, p. 314.
[1 ]Nizāmī, Chahār Maqāla (transl. E. G. Browne), pp. 115–18.
[2 ]Al-Qiftī, p. 179.
[3 ]Ibn Abī Usaibi‘a, I, p. 315.
[1 ]Al-Qiftī, p. 179.
[2 ]Al-Sīrat al-falsafīya (ed. P. Kraus): see selections from this work quoted at the end of the preface.
[1 ]M. Meyerhof, op. cit., loc. cit.
[1 ]Al-Bīrūnī, Risāla (ed. P. Kraus), pp. 3–5.
[2 ]Ibn Hazm, al-Fasl fi ’l-milal, I, pp. 24–33.
[3 ]Nāsir-i Khusrau, Zād al-musāfirīn, pp. 72 ff.
[4 ]Al-Kirmānī, al-Aqwāl al-dhahabīya, quoted by P. Kraus in his edition of Rhazes.
[5 ]De Boer, De “Medicina Mentis” van Arts Razi.
[6 ]At Cairo, under the title Rhagensis (Razis) Opera Philosophica, pp. 1–96.
[1 ]No. 107 in al-Bīrūnī’s list.
[2 ]No. 91 in al-Bīrūnī.
[3 ]No. 128 in al-Bīrūnī.
[4 ]No. 112 in al-Bīrūnī.
[5 ]Nos. 108–11, 113 in al-Bīrūnī.
[1 ]A quotation from Plato, Theaetetus, 176 b.
Last modified April 10, 2014