“All things emit rays in all directions, and all things arise and exist through rays” – Al-Kindi, On the Stellar Rays, seems to refer to the photon and its unpredictable physics.
When we hear the word “light” today we immediately think of the photon. But analyzing Al-Kindi’s thought in depth we see that his idea of motion originates from stellar rays. More specifically, for Al-Kindi, every star emits rays in every direction; indeed, overall motion arises precisely from these stellar rays. Everything originates and exists thanks to such rays. All bodies, once touched by the star rays, in turn emit rays everywhere. Not only does every body struck by stellar rays in turn release rays, but it also becomes a “source” of rays. Which is also a source of movement.
Does Al-Kindi discuss changes in the state of matter?
No. Al-Kindi discusses collisions and the consequences of such impacts. Indeed, this is the foundation of Al-Kindiʼs thought: if the stars are the source, all bodies touched in a certain sense “resonate”. The collision of bodies produces sound, which spreads everywhere thanks to the rays… therefore because words are believed by men to contain an effect of motion, taking up this opinion again, we said that sound produced in actuality make rays just like other actual things, and by their rays work in the world of the elements just as other individual things do”.
Al-Kindi’s theory—according to which all bodies, once struck by astral rays, in turn emit rays in every direction—appears to provide a physical foundation for the Neoplatonic theory of the One and the Many. Anyway, was the universe a giant billiard table for Al-Kindi?
Well, this is also an old concept in today’s physics: don’t they build accelerators to make particles collide? As for Neoplatonic theory of the One and the Many, in a sense, you are right. In fact, this is also the opinion of many historians of philosophy.
I must admit, however, that while Damascius’s account is obsessive in the details of the scales and chains of beings leading up to the Unknowable, Al-Kindi is repetitive regarding his few fundamental axioms concerning starlight—at least to me. Now, having lost the thread of logic, I will limit myself to quoting: The movement conceived by Al-Kindi is however all in harmony, despite the enigma of the diversity of things.
Al-Kindi solves the enigma of the diversity of things, and therefore of information, by merging everything into one and thereby varying the contents of all places. In every different place, the content of the rays is different, but it derives from the total harmony of the stars. Did not Plato say that harmony resolves the enigma of the diversity of things?
What about the images produced by the gaze? Can imagination impress a form in such a way that the human will alter the normal course of harmony?
Al-Kindi: “First, after having conceived the image of the thing, you have to imagine the shape of the thing that you wish to impress upon the matter through your work. This may cause a difference in the rays which proceed from any individual onto things near or remote, and, therefore, the projection of the will in human endeavor adds something to the effect.”Al-Kindi tells us that the “gaze” comes not from the will, but from the heart. And we know that in ancient times when one spoke of the heart one meant the seat of “memory” not of the will. Al-Kindiʼs idea that the rays come from the gaze does not seem too bizarre to a modern physicist when investigating photons hitting the eye, as we have already seen in Alchemy and Modern Physics.
But since the stars are too far away, the information is just information, that is, in “act”…
Every place in the world contains the rays of all things existing in Act, yet things differ from one another, so the rays differ not in causes but in effects.
Since the sidereal source is too distant, what Al-Kindi calls the “effect” should manifest itself during conjunctions, as if it were a chain… here we are back at the Neoplatonic theory of the One and the Many.
For Neoplatonists, the true change and transmission is not in the sequence of links in a chain, but rather in the places of contact between the links or conjunctions. So, every existing form is matter of the next that “passes” in it.
.Al-Kindi stated that we contain an example of the stars even though we are not stars…
The first Latin translator uses the word exemplum which in Latin also means seed as well as example. When Al-Kindi says that we contain an example of the stars he could also mean what we mean by “seed” today.
The causes are few, the effects are countless, but always moved by the “movement”…
In fact, the rays differ from the effects and not from the cause. Everything receives a form, sown in advance through movement (which the Latin translator calls motus). The stellar rays dispense a movement-motus in the material, called the Body of the Son. The cause influences the childʼs body through movement.
For Al-Kindi, the movement leaves its mark like a mold. … Nonetheless, when Al-Kindi spoke of the property of “rays” to impress “forms” on things, he already seemed to indicate a property of transporting instructions. Not exactly pertinent to the common light, but if we examine the wave functions of the photon…
Al-Kindi says: “Every existing form is the matter of a thing that closely imitates it, and the form passes into it by the action of rays” that “imprint” the form. This property is more properly attributed by the alchemists to air. When Al-Kindi speaks of the movement of the stellar rays which dominate and of different matters which receive through the movement a different form, we cannot but think back to what he said about sound. A modern physicist might read this “shape-imprinting” feature not only as impressions in the air, but also as packets of information that the photon seems to be able to carry.
I continue to quote: “… And since there are innumerable differences of sounds, each of them actually pronounced has its effect on elementary things which is different from the effect of the others… Therefore, since men believe that words contain an effect of motion, taking up this opinion, we said that the sound actually produced creates rays just like other real things, and with their rays operates in the world of elements just as other individual things do.” Is al-Kindi referring here to the unaware hearing of standard voice in a standard speech?
I will answer you by quoting Al-Kindi as well: “All sounds have an effect, but unless the effect reaches a certain threshold of power, no one takes any notice and uses the effect, and no one gains the benefit of the effect.”
Maybe voice modulation could be defined as a “manual artifice”, like handwriting?
Manual operations harmonize the elementary elements with the effect of movement. The writing of characters and figures done manually and with intention and in a ceremonial way has an effect of motion on external things. And this is because every form impressed in matter produces rays that cause motion in all things. And every figure has its own nature different from the others, just as their forms are different. And it causes motion in the bodies placed outside through the rays that it emits.
Does Al-Kindi mean here not only handwriting but also hand drawing?
We have seen how, through manual work, effects of movement are produced on things. Celestial harmony informs the image thus created through the projection of its rays. Therefore, even images, figures drawn manually emit rays into matter.
Taking it to the extreme: What about death by the hand of man? Can we also define this as manual labor?
Death by the hand of man alters the normal course of harmony. Here the responsibility is tremendous and can hardly take into account all the “deviations” of emanated rays.
We have seen how, for Al-Kindi, the different places and the different contents continue in turn to generate new sources. Could this be due to the power of straight lines and weakness of angles of incidence…
According to Al-Kindi, every star emits rays in every direction, whose diversity, fused into one, varies the contents of all places. In fact, in every different place, the content of the rays is different, which derives from the total harmony of the stars. For Al- Kindi rays are like straight lines, the straighter they are the more powerful they are. The ray that hits the center of the earth is very powerful, gradually weaker depending on the angle of incidence, unless the influence of another star intervenes. Since the stars are not all the same, so the rays coming from each star are different. Each star has its own position in the world machine.
So Al-Kindiʼs sidereal rays deviate once they hit the Earthʼs crust?
Well, no. We discover that Al-Kindi does not mean the Earthʼs surface but the very abyssal center of the Earthʼs sphere. The sidereal rays penetrate the earthʼs crust and powerfully reach its hidden centre, where they do not remain but rise to the surface.
But, before any form of deviation, what is a straight ray for Al-Kindi?
A line does not simply join two distant points, but places two points exactly opposite each other. In this way, stellar emissions become straight rays, point by point.
And then straight lines become surfaces…
The surface represents everything that has an extension, with the added property of altering and rippling.
… And in this movement the forms can travel…
Not only the forms can travel, but the previous form becomes matter for the next. A concept that is a bit difficult to understand if one does not admit that, for Al-Kindi, form and matter are not very distant concepts.
For Al-Kindi, the rays that penetrate the earth behave similarly to the gaze that receives and emits rays…
Al-Kindi: “The eye cannot see except along straight lines. Therefore it is necessary that, from all the points which are on the surface of the thing seen, it is possible to draw some straight lines to all the points on the surface of the eye: which is nothing more than to send and receive rays”.
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