Argument#9
Statement No. 9
Attraction, repulsion, and the center of rotation
Explanations and summaries are editorial material. Consult the source to verify the original wording.
Faithful reading
Statement No. 9: They want the matter to be understood in this way: because of what the source calls the body's "power of centralization," the body holds back from the effect of attraction and thus stands against the power of repulsion; through the combination of these two, it revolves around the center. The description of this follows later. But before the body had revolved, where was the center because of which the repulsion would occur? According to this account, that center would be specified only after the revolution had been completed. We will discuss the center and the Sun in Chapter I because, in the author's view, their contention about them is misleading.
Easy explanation
Imam Ahmad Raza (rahmatullahi alayh) is examining a particular explanation of how a moving body goes around a . In that explanation, and a separate are both given a role, and their combined action is said to produce a around the center. His first concern in Statement 9 is not to build a complete modern theory of motion. He is asking whether this explanation is arranged in a sensible order.
Start with attraction. In ordinary words, attraction means a pulling effect. The English source also speaks of a “” belonging to the body. That is wording from the model being discussed. It should be read as part of that model, not quietly turned into a standard modern physics term.
The same model then introduces a repulsive tendency as something separate from attraction. In simple words, it is presented as an effect that works away from the pull or resists being drawn inward. Statement 9 treats this as a separate part of the explanation. So it is safer to understand it in the source's own sense rather than rename it as some later scientific idea.
Next comes the revolution. Here revolution means the body going around a center. The model says that attraction and the separate repulsive tendency work together to produce this going-around motion. The center is therefore not just a word added at the end; it is already being used in the explanation of how the motion happens.
This creates the key difficulty that Imam Ahmad Raza (rahmatullahi alayh) wants the reader to notice. The claimed repulsion is connected with the center, and that repulsion is also said to help cause the revolution. If the repulsion needs the center in order to work, then the explanation seems to need the center before the revolution has been completed.
He therefore asks, in effect: before the body had completed its revolution, where was the center because of which this repulsion was supposed to occur? He then says that, according to the account he is criticizing, the center would be specified only after the rotation was complete. This is a cause-and-result question: can something be used as part of the cause if the same explanation says it becomes specified only after the result?
A simple comparison makes the objection easier to see. Imagine an instruction saying that a door opens because it reacts to a mark on the floor, but then saying that the mark is drawn only after the door has opened. The problem is not the door or the mark by themselves. The problem is the order in which the explanation asks us to use them. Imam Ahmad Raza's objection is about that kind of order inside the model he is discussing.
One modern clarification can help without changing the book's argument. If a path is already defined around a known point, we do not always have to wait for one complete round before calling that point the center. In simple physics language, motion along a round path is called . This clarification is separate from Imam Ahmad Raza's wording; it only helps us see that his objection is aimed at how the particular model connects the center, repulsion, and revolution.
At the end of Statement 9, Imam Ahmad Raza (rahmatullahi alayh) postpones the wider discussion of the center and the Sun to Chapter I. That boundary is important. Statement 9 has a narrower task: understand the model as it is presented, notice the order in which it uses attraction, repulsion, the center, and revolution, and then ask whether the center is being made to do explanatory work before the same account says it has been specified.
Start with attraction. In ordinary words, attraction means a pulling effect. The English source also speaks of a “” belonging to the body. That is wording from the model being discussed. It should be read as part of that model, not quietly turned into a standard modern physics term.
The same model then introduces a repulsive tendency as something separate from attraction. In simple words, it is presented as an effect that works away from the pull or resists being drawn inward. Statement 9 treats this as a separate part of the explanation. So it is safer to understand it in the source's own sense rather than rename it as some later scientific idea.
Next comes the revolution. Here revolution means the body going around a center. The model says that attraction and the separate repulsive tendency work together to produce this going-around motion. The center is therefore not just a word added at the end; it is already being used in the explanation of how the motion happens.
This creates the key difficulty that Imam Ahmad Raza (rahmatullahi alayh) wants the reader to notice. The claimed repulsion is connected with the center, and that repulsion is also said to help cause the revolution. If the repulsion needs the center in order to work, then the explanation seems to need the center before the revolution has been completed.
He therefore asks, in effect: before the body had completed its revolution, where was the center because of which this repulsion was supposed to occur? He then says that, according to the account he is criticizing, the center would be specified only after the rotation was complete. This is a cause-and-result question: can something be used as part of the cause if the same explanation says it becomes specified only after the result?
A simple comparison makes the objection easier to see. Imagine an instruction saying that a door opens because it reacts to a mark on the floor, but then saying that the mark is drawn only after the door has opened. The problem is not the door or the mark by themselves. The problem is the order in which the explanation asks us to use them. Imam Ahmad Raza's objection is about that kind of order inside the model he is discussing.
One modern clarification can help without changing the book's argument. If a path is already defined around a known point, we do not always have to wait for one complete round before calling that point the center. In simple physics language, motion along a round path is called . This clarification is separate from Imam Ahmad Raza's wording; it only helps us see that his objection is aimed at how the particular model connects the center, repulsion, and revolution.
At the end of Statement 9, Imam Ahmad Raza (rahmatullahi alayh) postpones the wider discussion of the center and the Sun to Chapter I. That boundary is important. Statement 9 has a narrower task: understand the model as it is presented, notice the order in which it uses attraction, repulsion, the center, and revolution, and then ask whether the center is being made to do explanatory work before the same account says it has been specified.
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