Q&A: Between Modern Physics and Aristotelian Physics
Between Modern Physics and Aristotelian Physics
Question
Hello Rabbi,
I’m asking as someone ignorant of both modern physics and ancient physics. It is commonly said that whereas Aristotle gave physics a reason in the sense that matter “strives” to return to its source and that this is its “purpose,” physics since Newton no longer speaks philosophy at all, only mathematics. When Newton describes his laws, he is not describing laws of mechanics to which one can give some kind of meaning. Nobody then knew what gravitation was, but they could write it in equations and test it experimentally. That is, physics at present is not fully understood, but it can be described mathematically and tested empirically. Science has given up trying really to understand *why* something happens as it does, and instead makes only deeper attempts at the how.
It seems to me that this is true only in physics. In biology there is much more “why.” Am I right? Is everything I wrote nonsense and chasing wind? In the Rabbi’s opinion, what is the difference between the old physics and the new, or is there no difference?
Thank you very much.
Answer
You mixed together different things here. Aristotle used teleological descriptions (in terms of goal or purpose, rather than causes). Modern science sometimes uses cause and sometimes purpose (although many scientists think it does not). But this has nothing whatsoever to do with mathematics. There is mathematics of purposes, and there are non-mathematical descriptions that are causal. Aristotle’s theory too (at least certain components of it) could be tested in the laboratory, and it’s a shame they didn’t do that, because then they would long ago have understood that he was wrong.
The difference between why and how is not sharp. But it is true that with Aristotle there is more why and less how.
And indeed it is true that in biology there is more why (teleology). But nowadays it is commonly thought that this is only a form of description that is convenient for us, while the truth is causal in biology too (because at root everything is physics).
Discussion on Answer
Functionals, as in analytical mechanics or Fermat’s principle. And of course potentials too.
Interesting! I’d appreciate it if you could be more explicit. What aspect of purpose is contained in functionals or potentials, and how is it expressed in them?
Just one small emphasis, so I won’t be misunderstood. I am intentionally asking about the mathematical terms you mentioned, not about Fermat’s principle or analytical mechanics. About the teleology of the latter, as ideas in physics, one can speak separately.
I don’t understand the purpose of this discussion; to me it looks like pointless babble, and probably trolling. These mathematical tools are used in physics with a teleological meaning, so these are not two different questions.
In short, if you know the subject, then this should be self-evident to you and there is no need to explain. If you don’t know it, this is not the place for it.
By the way, I explained this at length in The First Foundational Principle, at the end of the third conversation.
That’s it.
Your response boils down to: “If you know the subject, you should know that I’m right, and if you don’t know the subject, it’s not worth talking to you about it here.” Where is that coming from? Come on now, not everyone who asks you to explain something is trolling you, and not everything that is clear to you must necessarily be clear to everyone else. I have no doubt that you think you’re right. You can be sure that I think there is a lot of truth in what I’m about to write here on the substance of the issue, though I won’t claim too much confidence regarding the physics. Still, asking you to explain something in the place where you said it is neither a sin nor trolling. Quite the opposite. That’s what one is supposed to do in a substantive discussion. If that weren’t so, then Ilam Gross would be the glory of intellectualism.
As for the substance: I know the mathematical side of these things, and it is not at all clear to me what mathematics has to do with teleology. What does the calculus of variations have to do with purpose at all, and what do functionals and potentials have to do with purpose? The connection is not self-evident to me, and in the absence of an explanation from you of how you see these things, it will remain not self-evident to me. The question of what mathematics of purposes is is still on the table.
From the outset, it was clear to me that physical interpretations of these mathematical terms in certain models of physical phenomena can contain teleological aspects. Can. That needs to be established. In any case, I tried to put that aside, because you also said something about mathematics, and I see no reason to mix the discussion about mathematics with the discussion about physics.
I’ll note that I read the passage in question in The First Foundational Principle. I’ll emphasize that if you explained there what mathematics of purposes is, it escaped me. You are welcome to refer me to the relevant page and paragraph where you do so. The book is on the shelf beside me, and I’ll read it again.
Since it is pretty clear that you are a troll, I’ll add one short explanation and with that I’m done.
There are quite a few areas in physics where the dynamics can be described by means of functionals. In quantum theory, but also in classical analytical mechanics, and of course in optics (Fermat’s principle). The use of functionals essentially assumes that the physical object “chooses” the path that will lead to the minimal/maximal value of the functional. In that sense, this is a teleological description of the dynamics. Obviously the teleology is not on the mathematical plane, and I didn’t write that either. It is found in the use that physics makes of it. But the claim that teleological theories do not have a mathematical toolbox is nonsense. And that is what I wrote. I assume you understood all this perfectly well (if, as you say, you know these physical tools), and probably just decided to troll. So that’s it, I’m done.
By the way, causality too is not found in the mathematics but in the interpretation physicists give it. Newton’s second law, which describes a relation between acceleration and force, does not determine which is the cause and which is the effect. To us it is obvious that the force is the cause and the acceleration is the result, but that is only an interpretation of the mathematical equation.
What is mathematics of purposes?