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Suppose ball 1 collides with ball 2 which was at rest.

Then, ball 2 starts to move too.

It is as though the effects property of movement was already contained within the cause and got transferred.

Is this a coincidence? Or does this have a logical underpinning?

Is it (thus) the case that if X causes Y, the properties of Y must already have been contained in Y?

Does it follow that if X causes Y, both share a common property, namely the one the cause possessed that was transferred to the effect?

If one were to model a causation logically via sequent calculus, one could use the property of (cut-free) proofs that the proven statement is a subformula of some premises, which indeed would imply the above question, assuming all components could be perfectly encapsulated as logical statements.

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    Maybe useful Inferential Theories of Causation. Feb 23 at 14:18
  • @MauroALLEGRANZA Thank you very much, you have shown me what I was looking for, for some time. Feb 23 at 14:27
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    You are welcome :-) SEP is always a valuable resource. Feb 23 at 14:28
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    The idea that a cause transmits properties to its effects was popular in the middle ages and is known as transmission theory of causation, see Lloyd. It fits Aristotelian efficient causation but not so much modern conceptions, where cause/effect simply conform to laws of nature without any "transmission". However, some authors defended a version of transmission theory recently based on conservation laws, see Ardourel for discussion and criticism.
    – Conifold
    Feb 24 at 5:35
  • I beg you to find a colleague more comfortable with the concept of cause and effect, or with English; preferably, both. I suggest the Question title gives too much scope and the exposition can work in English only in terms too general for clear Answers. As it stands, the OQ might best be matched by responses such as Julio Di Egidio's (below)… and just think what you've already made of that! Feb 24 at 18:39

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In an aristotelician setting, and if understand your question correctly, this would be the case.

For a property, Aristotle distinguishes between its potentiality and its actuality. Typically, as in your example, a ball at rest would be moving potentially--as, while it is not moving right now it has the property of being able to move. After the impact, the ball would be moving actually. And so, before and after the impact, we are speaking of a same property but with different levels of realization. The wikipedia page gives you some helpful informations.

Obviously, this distinction opens many other questions. Regarding the different levels of potentiality (I am potentially playing the piano but, in a way, not as much as the real pianist who is just taking a break), regarding the relation between those levels as well as between potentiality and actuality (the wood is potentially a house, but this potentiality only exists because the house exists and so things may seem a bit in reverse order) and so on. But at least this provide a frame for the development of Aristotle metaphysics, which itself spans many books.


As an addendum, I would advise you to proceed with caution when reasoning informally with formal logic. In your last paragraph, you correctly observe that your statement would only hold if

all components could be perfectly encapsulated as logical statements.

But, in a way, this assumption is directly equivalent to saying that there is a common property (which can moreover be formalized); in particular this tautologically implies that there is a common property. In the end, we just said that if A then A.

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You consider the case that one moving ball hits a second ball at rest, and now the second ball moves while the first is at rest. This a standard experiment from mechanics and works best under the assumption that both balls are elastic, e.g., metallic, and both have the same size and mass.

Your question:

What is transferred from the first to the second ball during the kick?

In the history of physics it took some time to develop the two different concepts of momentum and kinetic energy, which govern the transfer and answer the question: Before the kick the first ball had non-zero momentum and non-zero kinetic energy, afterwards the same quantities with the same amount characterize the movement of the second ball.

Hence momentum and kinetic energy were transferred from ball 1 to ball 2. It was an important step to formulate both concepts as a function of mass and velocity of each ball, and to observe that the numerical value of these quantities is conserved.

This observation generalizes to the methodology to study the interaction of physical systems under the question:

Which physical quantities are conserved during the interaction, and how do other quantities change numerically?

It became one of the basic questions of physics. For an introduction see conservation law.

Added: But it would be misleading to ask for every interaction between two elementary systems A and B: Which properties are transferred from system A to system B?

For an example consider a high-energetic photon, system A, which under certain circumstances changes into a pair of an electron and a positron, which form the system B. The electron and the positron carry the electrical charge resp. +1 and -1 in given units, but the original photon has electrical charge zero. Hence the view of a charge-transfer is misleading. Much more useful is the insight that the sum of electrical charges is conserved: Before and after the interaction the sum is 0=1+(-1). This type of interaction is a common object of investigation in the field of quantum field theory.

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  • I think if we want to more generally address the question (for which the colliding balls were I believe more of an example), we could also speak of inertia. Behind this tried and approved concept is Newton first law and it would be the latent property which implicitly supports this causality.
    – Johan
    Feb 24 at 19:04
  • @Johan Inertia is the property of massive objects to keep their state of motion - you point to the first axiom of Newtonian mechanics. But inertia is not a property transferred from the cause to the effect.
    – Jo Wehler
    Feb 25 at 4:10
  • No indeed, I rather meant that inertia was the common property which supports the kinetical transfert (and so, more generally, the cause-to-effect relation). I feel like the question was raising a good point in saying that for X to cause Y there must be something shared before the causality and which precisely provides a ground for said causality.
    – Johan
    Feb 25 at 14:59
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In physics objects can have properties such as momentum and energy which can be transferred between objects when they interact. That does have a logical and experimental underpinning, which you can read about by googling conservations laws.

However, those are special cases. There is no general reason for properties to be transferred from a cause to an effect. A given cause can have multiple, mutually inconsistent effects, which seems to rule out the possibility of a conservation or transfer rule. For example, listening to a speech by a politician can cause cheers of admiration in some, jeers of contempt in others, or utter indifference. I would struggle to find a logic in which some property possessed by the politician is consistently transferred to individual members of their audience.

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Suppose ball 1 collides with ball 2 which was at rest. Then, ball 2 starts to move too.

But motion is relative, indeed "at rest" itself is a state of motion, and the actual physical process here is two balls with different trajectories and momenta colliding and both changing their state of motion.

It is as though the effects property of movement was already contained within the cause and got transferred. Is this a coincidence? Or does this have a logical underpinning?

In logic we can compose arbitrary implications and there is no necessity that the premise be even related to the conclusion.

I rather think a good approach to start seeing what is relevant to a cause->effect statement, as to "transfer of properties", is thinking in terms of necessary vs sufficient conditions.

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    Or perhaps, if one may abstract away from momentum which has concrete constraints (uncertainty, relativistic dilation...): What about state change itself. No thing can be its own change due to identity, thus some other thing must convey the new information. But then the information in the new state is a function of the external cause, thus a transfer happens the same way a variable is transferred in a function application. Feb 23 at 14:31
  • @MyersHertz I think that gets us farther away from the question. Besides that I'd object to the reduction of this problem (and of most problems) to a physical problem, as to the necessary reciprocity of physical dynamics just think Newton's third law. There rather is a notion of system in physics... OTOH, "no thing can be its own change due to identity" I'd think is a meaningless statement: I could ask what "identity" do you have in mind. Feb 23 at 14:52

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