October 31, 2010

A description of the rain

Abu Hatim tells us that Abu 'Ubayda said:
One day Al-Nu'man sallied forth after a rainstorm. On meeting with a mounted desert Arab on his camel, he hailed him, and the Arab obeyed his summons. Al-Nu'mān said: "How is the land that you have left behind you?" "Wide and spacious," said the Arab. "With easy lowlands, rugged hills and mountains firmly rooted, it is a capable sustainer of what sits on it." Al-Nu'mān said: "But I was asking you about the sky."

"It is high and free-standing," the Arab said, "without the aid of poles or tent-cords. Its day and night are clearly separated, and its sun and moon follow each other in succession." Al-Nu'mān said: "That's not what I’m asking you about!" "So ask what’s on your mind," the Arab said. Al-Nu'mān said: "Has rain been falling there, and if so can you describe it?" "Yes," the Arab said.

"The sky rained on our land for three long stretches without budging. It soaked it, left it swampy and then left it ankle-deep. Then I went forth from my people, and searched the land and found no part as far as Tish'ār that was spared. The clouds boomed out to one another on every side, and heavily the flow drave on, erasing the roads and filling the hollows, and digging the trees out at their roots. All souls kept to their shelters, and no traveler could depart until the sky left off harming us with its blessings. When solid land had re-emerged, and pathways through the fields could be descried, I came out to observe the sky and every quarter of its rim. No refuge could I find except for caverns in the hills, for the jarr al-dabu'* had been disgorged: the lowlands were like seas of slapping waves, the rugged hills were wrapped in flotsam, and carcasses of wild animals were flung in all directions. And I did not leave off treading the sky’s residue and wading its water until I reached your land."

*Abu Bakr said: The meaning of jārr al-dabu' ["The Hyena Driver"] is that it forces the hyena out of its underground lair.

Abu Bakr ibn Durayd, The Book of the Description of Rain and Clouds, ch. 14.

October 28, 2010

Al-Kindi on the rain, and why it seldom falls in Egypt

You ask (may God illuminate your pathway to the truth) what causes some places to get hardly any rain. If the cause for abundance of rain in some places were to be made plain to you (may God guide you aright), you might also appreciate (may God reveal to you all that is hidden) the cause for a prevailing lack of rain in other places, since it is in combination that contrarieties become known.

[...] All bodies undergo contraction when chilled, after which they need a smaller place than the one they occupied before their chilling. When heated, they undergo expansion, and need a larger place than the one they occupied before their heating. Therefore does air flow from a hot, expanded location toward one that is cold and contracted, and this flow is what we call the wind (for our usage gives the name of "wind" to the flow of air and "wave" to the flow of water). This explains why the wind is greatest when the sun's heat is shed along its southern inclination: expanded by that heat, air from the south flows north to where the air has been chilled by its remoteness from the sun.

When the sun is in its northern inclination it heats the areas to the north, and those in the south become chilled. The northern air then expands and flows in the direction of the south, due to the cold-induced contraction of the air there. For this reason, most summer winds are northerly winds, and most winter winds come from the south – except for winds which arise (in some cases all at once, in others little by little) from such sublunar factors as the course of rivers, the occurrence of floods, [and the influence of] stagnant waters, open meadows, the sun’s reflection on the tops of stony mountains, irrigation, agriculture, woods and wetlands. These factors (and others like them) contribute to the flow of vapor in different directions, which the various winds distribute according to the disposition of the earth’s territories (high places and low, caverns and open places), the influence of any fires burning therein, and so on.

The vapor made to flow across the face of the earth by the sun’s alternation between north and south was likened by ancient Greek sages to a freshwater sea of alternating tides, and they called it Okeanos, the earth-encircling sea.

When vapor ends up in a place whose distance from the sun’s path chills the air to the point that the vapor’s volume is reduced, the vapor becomes thick and dense and is converted into water by the air around it, which releases it in the form of rain upon the earth (along with any particles of earth taken up as earth-vapor). Meanwhile, these vapors crowd the air with their weight and set it moving, turning it into wind (which is the flow of air).

Vapor attains its maximum degree of density when it flows into caves or between mountains where its flow is hampered by the cold, or checked by an opposing flow of air, in the way that vapors have of being redirected by sublunar factors (as we have already described). But if vapor winds up in a location devoid of what reduces its volume and chills it, it spreads beyond that location until it encounters what we have defined as cold, condensing factors -- whether or not the land itself accumulates much standing water. For vapor is raised from the earth every day the sun casts it heat, and after it sets even more moisture may be released in the form of dew, having been attracted in the form of vapor that flows in from elsewhere, as happens daily in all forests.

As for those locations (be they in the south or elsewhere) whose moisture falls short, devoid as they are of any means of containing the vapor flowing into them from the south (due to the lack of high encircling mountains to the north) and furnished as they are with continual air currents (either by the influence of great quantities of moving water or the nearness of a body of water at its northern end), – locations in which the flow of vapor is diverted elsewhere due to some stronger flow prevailing against its wonted northward course – the presence of rain in those locations is very small. So it is in the country of Egypt, whose air on the north side lacks high mountains, and where most of the vapor flowing south to north (from the Sea of Abyssinia) is deflected by the mountains of the Beja (such as al-Muqattam and the mountains near it), so that the Sea of Abyssinia’s vapors flow towards Iraq.

From the treatise On why some places almost never get any rain

October 11, 2010

By the author of Aristotle Among the Arabs

I came into this world by chance, and by chance I will depart it. One proof of this is that if my father had not stooped to recover a blown sheet of paper that drifted to the ground one October day in 1913, he would have lost his life. On the evening of that day, an assassin hired by one of his enemies came near his seat in the mayoral house and fired a round of bullets at him. At that very moment, the sheet of paper he was reviewing (which was a brief from the shari'a court) took flight - and at the moment he bent over to retrieve it, the bullets buried themselves in the door behind him, grazing only the edge of his turban. "Is God alive?" he shouted, and fell silent. The assassin, believing he had dealt my father a fatal shot, took off running for his benefactor's house. My father recovered instantly, however, and ran off after him, keenly surmising that he would be led to the house of a wicked adversary called Gado Zarad. Along the way he called out for people to join him on the trail, and in half an hour they had Gado's house surrounded. Half the village turned out and stormed the house, and when they did not find the perpetrator one of their number led an attack on an unroofed house next door where he had fled. The man was found hiding in a corner and was seized and bound with ropes, as was the man who hired him. And my father sent word to the police in Fariskor (some 80 km from Sharabass), who came and took the men into custody and drove them back to the station in Fariskor. My birth took place 40 months later, on February 4, 1918.

If you examine the life of any person, you will find that a kind of chance is what gives rise to his or her birth, i.e. the chance encounter between the spermatazoa of a man and the egg cell in a woman. Whoever concludes from this that there is order or intentionality or a plan is just a dreamer. All that's at work are causes, operating in competition with each other, engendering whoever is engendered and annihilating whoever is annihilated.

'Abdel Rahman Badawi, The Story of My Life, v. 1, ch. 1.

June 28, 2010

How rain is known as line and circle

One of the internal perceptive faculties that are proper to the living animal is fantasy [Gk. phantasia], which is the “common sense.” Its place is in the first chamber of the brain, where it receives into itself all that is conveyed to it from the totality of forms impressed on the five senses. Another faculty is positioned in the rear part of this chamber: this is the imagination [Ar. al-khayyāl], which is the form-producing faculty. It preserves what the common sense presents to it from the five individual senses, out of what remains there after the sensible objects are no longer present. It is well known that reception and preservation are the work of separate faculties. Think of water, which has the capacity to receive an imprint or an inscription and to take on any shape, but lacks the capacity to retain them (in a way that we will clarify later).

If you want to know the difference between the action of external sense generally, the action of the common sense, and the action of [the form-producing capacity of] the imagination, consider how you see the falling drop of rain as a straight line, and how you see the end-point of that cylindrical straight line as a circle. A thing cannot be perceived as a line or a circle until it has been looked into multiple times. External sense is unable to see it at two [separate] times, but sees it rather as it happens to be.
What is impressed on the common sense and passes away is perceived by the external sense as it happens to be. After it is effaced, its form remains in the common sense, which perceives it as if it were still there, just as when it happened to occur. The form-producing faculty sees an extended body which is spherical or straight, and this is something that can in no way be attributed to the external sense. The form-producing faculty perceives both matters, and gives form to them both, even when the thing itself no longer exists or is absent.

Then there is the faculty called "post-imaginative" with respect to the animal soul, and "cogitative" with respect to the human soul. This faculty is positioned in the central chamber of the brain, at the cerebellar vermis. Its characteristic function is that it combines and separates the contents of the imagination as it will. Then there is the estimative faculty, positioned at one end of the brain’s middle chamber, where it perceives the meanings [Ar. ma'ānī] which are not perceived through particular sensations. Such is the [above-mentioned] faculty present in the sheep, which determines that this wolf is to be fled from and that this lamb is to be cared for. It seems that this faculty is also what effects changes in imaginary objects, combining and dividing among them. Then there is the retentive, recollective faculty located in the hindmost chamber of the brain, which retains what the estimative faculty perceives in the way of meanings unperceived through particular sensations. The relationship of the retentive faculty to the estimative faculty is like the imagination’s relationship to the senses, and the relation of that faculty [the estimative] to the ma'ānī is like the relation of this faculty [the imaginative] to the sensible forms. These are the internal perceptive faculties of the animal soul.

On the soul (The Cure: Physics, book 6) I.5

Avicenna on extra-sensory perception

Reminder. The common sense is a tablet. When its surface is occupied by an impression, that impression is also made in the judgment of the beholder. Sometimes when the sensible object withdraws from the senses, its form remains for a while in the common sense and in the perceiver’s judgment, in isolation from the imagination. In this connection, you should recall what was said to you about the rain that falls in a straight line, and the circular impressions left by its scattered droplets. When, on the tablet of the common sense, the likeness of a form is produced, that form is then perceived, whether it is at the beginning of its state of being impressed from without, or persisting along with a persisting sensation, or as something fixed after that sensation has ceased. Alternately, [a form] might occur in the soul in a way that owes nothing to sensation.

Pointer. Forms that are present and available to external sense may be perceived by unwell and bilious sorts in isolation from the external sense-objects themselves, impressed on the soul through an internal cause which may or may not be influenced by some other cause. The common sense may also be stamped by a "wandering" form that strikes the seat of imagination and estimation; likewise, imagination and estimation may receive an impression from the tablet of the common sense. It is something like what happens between two mirrors that face each other.

Reminder. There are two causes that distract from this sort of impression. One is sensory and external; the other is produced internally by the intellect or the estimative faculty. In the former case, the tablet of the common sense is occupied by some other impression made upon it, effectively usurping [the attention] and wresting it away from the imaginary entity. In the latter case, the activity of the imagination is checked as the intellect or the estimation intervenes in what is occupying the soul, and the imagination is made compliant to it, and loses its power over the common sense. The imagination is no longer capable of making an impression on the common sense, for its movement is weak – something which follows, but is not itself followed.

If either of these two distracting faculties is stilled, the other one remains. It may happen that the remaining faculty is unable to check the imagination; in these cases, the imagination regains its power over the common sense, which is then taken over by signs of forms [such as are] beheld by the senses.

Pointers and Reminders 10.12-14

June 10, 2010

Avicenna on that helium

Reminder. From what has gone before, you know that the particulars are stamped on the intellectual world in their universal aspect. After that, you were led to notice that heavenly bodies are endowed with souls that have particular perceptions and desires proceeding from their particular point of view. There is no bar to their forming concepts of the particular concomitants that arise from their particular movements in the elemental world.

If this observation, concealed as it is from all but those whose intellect is stanched in elevated wisdom, is in fact true -- namely, that after the separated intelligences which are theirs as a matter of principle, they have a rational soul which takes in no material impression, and that furthermore these retain a certain connection, as between mortal souls and bodies, through which they are empowered to obtain a certain perfection; -- If this is true, then heavenly bodies are provided with a supplement, meaning that they present both a universal view and another view particular to them. What you should gather from these remarks is that the particulars do make an impression on the intellectual world in the form of a universal figure, and in the world of the soul the impression they make is time-sensitive and takes the form of a particular figure.

Pointers and Reminders 10.9

April 22, 2010

Al-Jahiz on inarticulateness

Animals are divided into “articulate” and “inarticulate,” though not in the sense those words are generally used in Arabic. They are so called in the way that “silent” is said without misunderstanding for what is not at all silent, and “speaking” is said for what never raises its voice. Whereas people speak with each other when they come together, animals use bellowing, bleating, braying, neighing, yodeling, mooing, whooping, howling, barking, crowing, meowing, grunting, screeching, hissing, yelping, clucking, croaking, roaring, razzing, rattling and hissing.

There are other instances [of words, like "inarticulate," that have more than one antithesis], such as dhukūr which means “males” as opposed to females, like the merchants’ caravan [in its separation] from the women’s caravan. Dhikr [pl. dhukūr] is furthermore what we call “the upper-handed” of any two parties that come face to face or take [their leave?] of one another.

The articulate animal is the human being. Inarticulate is every animal whose voice is only understood by other members of its genus. We, I aver, understand many of the desires, needs and aims of the horse and the ass, the dog and the cat and the camel, just as we understand the desire of the baby in his cradle, knowing (and it is an exalted form of knowledge) that its crying signifies something different from what is signified by its laughter. Also we understand that the horse’s whinnying when it sees its feed-bag is different from its whinnying when it sees a mare, and that the cat’s call to the tomcat is different from her call to her young. And examples of this are many.

Human beings are articulate, even if they express themselves in the language of Persia or India or Greece. The Greek understands clear Arabic no better than an Arab understands the Greek's outlandish speech. In this sense, all people may be said to be “articulate.” When they say “inarticulate,” distinguishing it not from “articulate” but from “Arab,” they do not have this meaning in mind. Rather, they mean that the “inarticulate” man does not speak Arabic, and that an Arab cannot understand him. And Kuthayyir says:

   Fa-būrika mā a'ta 'bnu Laylā bi-niyyatin
      wa-sāmitu mā a'ta 'bnu Laylā wa-nātiquhu


   In what Ibn Laylā gives off there is no way for you to learn his intention.
      What Ibn Laylā gives out is of two kinds: silent, and vocal.


When they say: “He came bringing what is loud and what is silent,” the “silent” refers to [inanimate goods] like gold and silver, and the “loud” refers to any animal. Here it means he spoke, and fell silent. “Silent” refers to anything [in the way of capital] excluding live animals.

Considering what is in the world, we find its existence to be [the product of God’s] sagacity, and of [the products of] that sagacity we find two kinds: the thing that has no concept of sagacity or what it entails, and the thing that does conceive of sagacity and what it entails. The thing that conceives and the thing that has no concept are equally signs of [God’s] sagacity, but they are different from the standpoint that one is a sign that lacks the power of inference, and the other is a sign that has that power. As signs which lack the power of inference, animals (with the exception of people) are aligned with inanimate matter. To be a sign that also has the power to infer from signs was given to people. A connector was then made to be their guide to the various aspects of inference from signs and what results from inference. And that is what they call “intelligibility” [al-bayān].

The Book of Animals I 31-33

January 5, 2010

Avicenna on writing, speech, and psychic trace

"Human beings are endowed with a perceptive faculty on which the forms of external matters are impressed. From there the forms are conveyed to the soul, where a second impression is made, one which persists even when those forms are no longer present to the senses. Now matters may be impressed on the soul in other ways which resemble the conveyance of the senses, as when an impression is made on the sense, and its sensible form is subsequently converted into an abstraction; alternately, impressions may come along another route which it is not the job of logic to explain.

"Matters have an existence in themselves and an existence in the soul, which leaves traces there.

"Out of its need for association and community, human nature is dependent on communication, and was motivated to contrive a means to it. [To that end] there is nothing swifter than the action of the voice, which is especially well adapted given the voice's evanescence and impermanence, and its lack of simultaneous plurality. In addition to its swiftness, it has the benefit of enabling semiosis, along with its effacement when the need for signifying has passed (lest it be construed as a signifier after this). Therefore nature inclines toward use of the voice, and is outfitted by grace of its Creator with the instruments for articulating phonemes and arranging them so that the traces in the soul are signified.

"After that there follows a second need, and that is for a path to knowledge of what is currently inapparent or still to come in the future. What is learned in the future can be added to the record of things already known, for the benefit and completion of humankind’s wisdom through mutual association. Most of the arts are only brought to completion by the development of the ideas they contain, and the discovery of their laws, with the latecomers assisted by the predecessors in whose footsteps they follow, and this is to the benefit of those still to come. Even what is not currently needful may prove useful. Some other path to knowledge besides speech was therefore needed, so the various forms of writing were contrived, all by divine guidance and inspiration."

"The signification of real-life matters within the soul is a natural mode which does not vary as to its signifier or signified, as does the utterance's signification of the psychic trace (in which the signifier does vary although the signified does not), nor is it like writing's signification of the utterance and writing (in which signifier and signified alike may vary).

"As for the process by which the soul imagines the forms of real-life matters and what sets that process in motion, and what it is that attends to the forms when they are inside the soul, and what attends to them when they are outside, and what the causal agent is that rouses the imaginative faculty to actuality -- these questions do not pertain to logic but to another field of knowledge. Likewise, the arbitrariness of speech and writing may be debated by linguists and scribes, but the logician speaks of it only in passing. The aspects of utterance which the logician does need to know about are the conditions by which simple and composite meanings are indicated, in order thereby to gain insight into meanings themselves, the better to gain insight from them into the unknown. For this is the logician’s job."

From On interpretation (The Cure: Logic, book 3), I.1

June 14, 2009

Avicenna on form vs. meaning

"As for the internal perceptive faculties, some are for perceiving the forms of the sensibles and some for perceiving their meanings. Among these faculties, some perceive and act, and some perceive without acting. And some of them exercise primary perception and some secondary.

"The difference between perception of form and meaning is that form is what is perceived by exterior sense and interior sense together, though the exterior sense perceives it first and conveys it to the interior sense – like the sheep’s perception of the form of the wolf, by which I mean his shape and semblance and color. And so it is perceived by the sheep’s interior sense, but only after the exterior sense’s perception of it. As for meaning, it is what the soul perceives out of what is sensed, but which exterior sense does not itself first perceive. Such is the sheep’s perception of an antagonistic intention in the wolf, or the meaning which necessitates its fear of the wolf and avoidance of him, without any report of the senses whatsoever. The name of 'form' specifies that aspect of the wolf which external sense perceives before the internal sense. And what the inner faculties perceive without sense is specified in this context by the name of 'meaning.'

"The difference between perception with action and perception without action is that certain internal faculties serve to combine and divide perceived forms and meanings, thereby playing an active role in what is perceived, in addition to mere perception. Inactive perception is where the impression of a form or meaning is simply received, without any alteration being carried out on it.

"The difference between primary and secondary perception is that form occurs to primary perception much as it does in the thing itself. In secondary perception, the form of a thing occurs in relation to some other thing, which is what conveys it."

From On the soul (The Cure: Physics, book 6) I.5, continued here.

May 12, 2009

Al-Farabi on potential intellect

"Aristotle speaks of four kinds of intellect in his book On the soul. These are potential intellect, active intellect, acquired intellect and agentive intellect.

"Potential intellect is a soul, or part of the soul, or one of the soul’s faculties, or a certain something essentially disposed for abstracting the quiddities of all existing things, and their forms without their matter. For some things it makes more than one form, but for all things it makes at least one. Only when this certain something assumes the forms which reside in materials do those forms become abstracted from their materials. When this happens, the forms are called 'intelligibles,' after the abstracting faculty [of the intellect] which assumes the forms of existing things.

"This certain something resembles the matter in which forms are actualized, with one big difference. Imagine some corporeal matter like wax with an impression stamped into it, such that the impression and its form are received in its surface and its depth, and the matter is wholly taken over by that form to the point that in its totality and as a whole the matter is permeated by that form and in fact becomes that form. If you imagine that, you are close to understanding how the forms of things are actualized in that certain something, which behaves like the matter and substrate of a form but differs from all other corporeal matters in that these receive forms in their surface only, and not their depths. In its essence this certain something is identical to the forms of the intelligibles, to the extent that it becomes them, even though the forms and the certain something retain their own dedicated quiddities. For this, imagine a stamp which imparts a cubical or spherical character to wax as it plunges into it, permeates it and takes over its entire length, breadth and depth such that the wax becomes that very character, and what the one is cannot be separated from what the other is. By this analogy, you should understand how the forms of existing things are realized in that certain something which Aristotle calls 'potential intellect' in his book On the soul."

From the Treatise on the Intellect

May 6, 2009

Al-Farabi on logic vs. grammar

"When by ourselves we wish to verify the truth of a judgment, we think and inform ourselves, and set up in ourselves the matters and concepts that serve to verify that judgment. When we do this with someone else, we perform the speech though which such matters and concepts may be understood.

"It is not possible to verify any judgment we may come to using just any concepts we happen to have, nor can we disregard their number nor the condition, composition and order in which we find them. Rather, for every judgment we seek to verify, we need matters and concepts which are well-defined, known quantities, and determination of condition, composition and order. This requires that the state of the words that express these be in the same state as the words we submit to one another for verification. For this, we need rules concerning our concepts as well as our expressions for them, in order to protect us from error. These two things – I mean concepts and the words which express them – are what the ancients called logos and speech. 'Intelligibles' are what they called the internal speech and logos implanted in the soul, whose outward expression is spoken speech and logos. When he is by himself, the speech which a man uses in order to verify a judgment is that which is implanted in his soul. When he does it with someone else, he gives voice to outward speech. The kind of speech that creates analogies in order to verify judgments is called 'syllogism,' whether its terms are implanted in the soul or spoken aloud. And logic imposes the above-mentioned rules on both types of speech.

"Logic shares with grammar its function of giving rules for utterances, but insofar as grammar gives rules for the utterances of a given nation, the science of logic is different since its rules govern the utterances of every nation. Now words present certain aspects that are the same for all nations, such as whether they are simple or compound, whether they are nouns, verbs or particles, whether or not they are endowed with meter, etc. But language differs from language in many ways: its case endings and article usage are only two of many features by which Arabic is distinguished from other languages. Every language is distinguished in ways like these. The domain of grammar does include features common to the utterances of every nation, but those who practice it take them up as encountered in terms of the language in which they happen to be working."

"By contrast, when logic gives rules for the use of words it does so for the words of every nation, which it takes up in their common aspects, avoiding those which are specific to one nation in particular. When logic does take up an expression specific to a given language, however, it does so according to the grammatical authorities on that language.

"As for the rubric 'logic,' the totality of its meaning is clearly announced in that it is derived from logos, a word said by the ancients to mean three different things:

1. Outward speech, spoken aloud. Its expression is made possible by the tongue.
2. The speech that is implanted in the soul, made up of the intelligibles that words signify.
3. The spiritual faculty instilled in man, by which he is distinguished from the other animals, and through which the intelligibles arise for him, together with the sciences and the arts. It makes judgment possible, and moral distinctions between good and bad actions. All men have this -- even children, though in children it is trifling since it cannot yet carry out all its functions. In this it is like the child's leg not wholly fit for walking, or a fire of low intensity which cannot yet ignite the palm branch. Even drunks and crazy people have it, though in them its purview is narrowed, and in the sleeper it has gone out. For the sufferer of a petit mal it is as if a veil had come between him and it."

From Catalogue of the Sciences, ch. 2

My Callousness

     A hundred steps I have to climb.
     Ascend I must, and hear you cry:
   "Cruel one! Made of stone are we?"
     A hundred steps I have to climb.
     A step is not much fun to be.

Friedrich Nietzsche, "Prelude in German Rhymes" (no. 26)
to The Gay Science