yar

Thanks for the responses. AisA, your explanation was much less convoluted than mine. With the thing I said about conservation of energy, I was just thinking of what relation the philosophical idea that "something can't be created from nothing" might have to conservation of energy when anything we call "something" must consist entirely of mass and energy. So I thought in that way it might possibly have a closer relation to philosophy than other scientific theories. But more importantly, I have no idea what I'm talking about and should be ignored . Science is doing just fine without me trying to derive it philosophically.

By "logically necessary" I meant, why there would be a contradiction in the possibility that a physical object's movement could be random in some way. By "any possible universe" I meant any conceivable reality, any universe which can be described coherently. I suppose even that's not all that clear. More specifically what I meant was that by the scientific method as traditionally understood, conservation of mass/energy isn't proven, just very well established. Since I saw some threads in which people were discussing physics earlier, I was wondering if anyone has an opinion on whether it's possible that conservation of mass/energy could be violated at some point, or if that's flat out impossible.

I've just started reading OPAR after having finished Atlas Shrugged recently, and I'm not entirely sure I understand the line of argument as to why causality is logically necessary (in chapter 1). I've read and completely agree with the section establishing the axioms of existence, consciousness, identity. As I understand it, the argument is that any attempt to disagree with the axioms must necessarily use the axioms (they are entailed in the statement "there is something I am aware of"), and I agree. The explanation of why identity entails causality is somewhat less clear to me. In order to explain an object's action (movement) as a function of something other than it's own properties and the properties of the objects it interacts with, I suppose you would have to say that its movement is caused by something, and if that something isn't a finite set a physical objects, then it would have to be something outside the physical universe, ie. "God" or "randomness". Is the Objectivist position that any statement which cannot be explained in terms of consciousness and a finite set of physical entities is meaningless, because there is nothing in our self-evident facts of existence that such a statement refers to? Given that, is the argument for causality that: to even conceive of something outside the bounds of the physical universe is irrational and nonsensical, and therefore the only factors that could possibly decide an object's movement are its own physical properties and the physical properties of objects it interacts with? Does anyone have anything to add to what I just wrote, as to why causality is necessary? On a somewhat different topic, are there any Objectivist physicists here who have considered to what extent our accepted laws of physics must hold in any possible universe? Is conservation of mass and energy logically required in any possible universe? Would a universe governed by Newtonian mechanics be contradictory?