biep@cs.vu.nl (J. A. "Biep" Durieux) (07/20/87)
___________________________________________________________________________ / \ | I found this in sci.physics. I think it belongs here at least as well -Biep | \___________________________________________________________________________/ In article <651@sri-arpa.ARPA> gould!proxftl!bill@seismo.CSS.GOV writes: From: gould!proxftl!bill@seismo.CSS.GOV (T. William Wells) This is my first message to be passed on this net, so let me give my background: fifteen years ago, I was heavily into mathematics and mathematical physics. I am no longer active in these fields, but from my readings I can say with confidence that there is not an aweful lot new since then. (Forget the replies: I am likely to be aware of whatever it is you consider significant; I probably do not consider it significant. As to why, see the sequel.) Nowadays, I am a computer programmer and an Objectivist philosopher (N.B. While my philosophy is based on Rand's, I am not a Randroid!) Having read a number of messages about the nature of QM, all of which miss the point as far as I am concerned, I decided to transmit my own. As any understanding of the nature of QM comes from philosophic consideration rather than from guesswork and speculation based on the material of QM, the remainder of my message is not physics; it is philosophy. Most of the problem in talking about QM comes from the fact that either the talker is essentially ignorant of philosophy or has, a priori, accepted some philosophic idea which, since it is at variance with the facts of reality, eventually drives him into some belief in the supernatural. I am going to demonstrate that QM is NOT a theory. To do so, I am going to make two sets of distinctions: between philosophy, theory, and model; and between the two different things meant by the word "QM". First, philosophy: the essential parts of philosophy are metaphysics and epistemology; they answer the questions of "what kind of universe do I live in?" and "How do I know?", respectively. The answers to these questions determine the other answers that a philosophy gives to the questions usually associated with philosophy. In particular, these answers allow one to distinguish between a potentially valid description of reality and a mere statement about facts of reality. The former is a theory; the latter is a model. As examples: " ... to say that the same thing acting on the same thing under the same conditions may yet produce a different effect, is to say that a thing need not be what it is. But this is in flat conflict with the Law of Identity. A thing, to be at all, must be something, and can only be what it is. To assert a causal connection between 'a' and 'x' implies 'a' acts as it does because it is what it is; because, in fact, it is 'a'. So long therefore as it is 'a', it must act thus; and to assert that it may act otherwise on a subsequent occasion is to assert that what is 'a' is something else than the 'a' which it is declared to be." [This is from "An Introduction to Logic" by H.W.B. Joseph, as quoted in "Atheism: the Case Against God" by George H. Smith. I will amplify the preceding statement by noting that the statement "if it is 'a' then it will do 'x'" has as its contrapositive: "if it does not do 'x' then it is not 'a'. Note that the quoted paragraph is metaphysics; my observation is epistemology.] The indented paragraphs are philosophic. They are parts of expositions on the relationship between the Law of Identity, a metaphysical idea, and Logic, a part of epistemology. Now, for theories: A theory is a statement about what exists and what its properties are. A theory must come into existence in a way which is prescribed by its underlying philosophy and must make the kinds of predictions which its philosophy demands of knowledge. Any theory is invalidated if one discovers a contradiction between it and its underlying philosophy. It is a characteristic of matter that it possesses the attribute of mass; the degree of this characteristic is proportional to the ratio between an applied force, and the resulting acceleration. This is an example of a part of a theory; note its form: it is almost a direct application of the Law of Identity, as expressed in the philosophic quote. In order to be a complete theory, it would have to describe the evidence by which we know of the existence of matter, force, and acceleration, and would have to express additional properties associated with mass (such as inertia, conservation, angular momentum, etc.). Finally, here is a model: When we apply formula 'x' to the variables 'a', 'b', and 'c' we find that the result is very close to the value of variable 'd'. Thus, this formula can be used (under the appropriate circumstances) to compute the expected value of 'd'. This, of course, is merely the observation that 'x' provides a good model for 'd'. It does not imply any causal relationship between 'a', 'b', 'c', and 'd' (though it suggests strongly that one should go looking for one). So here is the difference: a philosophy expresses an underlying view of reality and knowledge; a theory is knowledge about specific things, formed in accordance with its underlying philosophy; and a model is simply a relationship between variables, which may or may not have any reality. The second distinction I want to make is between the two kinds of things meant by QM. The first is found in any textbook on QM: a set of relationships between "observables" and some formulas, possibly adjoined with some justification for why these formulas and not some others. The other kind of QM is the one usually found in discussions among those who are my intended audience: this QM ignores the specific formulas and concentrates on the underlying assumptions of the other kind of QM and attempts to understand the reality presumed by these assumptions. Rather obviously, the first kind of QM is either a theory or a model; the second is a philosophy. As a model, any given set of QM formulas either predicts or does not; this is the standard of a model. If it predicts well (QED for example), it is a good model; otherwise not. As a theory, the first kind of QM fails miserably. It does not meet one important requirement of a theory: it is not consistent with its underlying philosophy. Since this kind of QM was derived from the kind of philosophy expressed in the philosophic quote I presented, its prediction that the Law of Identity is invalid is a contradiction. Of course, this contradiction is the whole reason for the existence of the second kind of QM. I could stop here, as I have already made my demonstration, but I want to make one final comment about philosophic QM. Philosophic QM comes into being because QM, the model, when considered as a theory, contradicts its underlying assumptions. Unfortunately, any evidence for philosophic QM will be filtered though the other philosophy, placing an unalterable contradiction at its root. The only possible out is to evaluate the whole of human experience in light of philosophic QM as the underlying philosophic system, to see if the system retains consistency. Actually, that too will fail: consistency is something demanded by the Law of Identity; deny the law, and you deny the need for consistency; deny consistency, and you deny the possibility of distinguishing existence from nonexistence and therefore truth from falsity, and ultimately the validity of philosophic QM. Therefore, any person who attempts to validate philosophic QM must eventually either give it up as a bad job or become a mystic. T. William Wells Proximity Technology Inc. seismo!gould!novavax!proxftl!bill P.S. To forestall irrelevant comments, here is my definition of mysticism: a philosophic system whose standards are unconcerned with or in contradiction to the evidence of one's senses. This makes religious philosophy, materialism, skepticism, and rationalism (to name a few) mysticisms. ------------------------------------------------------------------------------- -- Biep. (biep@cs.vu.nl via mcvax) Popper tells us how science ought to be done - Kuhn tells us how it *is* done. And I ... I read neither.
laura@hoptoad.uucp (Laura Creighton) (07/20/87)
>In article <651@sri-arpa.ARPA> gould!proxftl!bill@seismo.CSS.GOV writes: > >First, philosophy: the essential parts of philosophy are metaphysics and >epistemology; they answer the questions of "what kind of universe do I live >in?" and "How do I know?", respectively. The answers to these questions >determine the other answers that a philosophy gives to the questions usually >associated with philosophy. In particular, these answers allow one to >distinguish between a potentially valid description of reality and a mere >statement about facts of reality. The former is a theory; the latter is a >model. I think that this gives philosophy too short an end of the stick. My current thought project is dividing human persuits into a quest for answers of the three questions ``What is Beauty'' ``What is Truth'' and ``What is Goodness''. ``What kind of universe do I live in and how do I know'' is fundamental to the Truth question, but does not (or at least not trivially) relate to the Goodness and Truth questions. -- (C) Copyright 1987 Laura Creighton - you may redistribute only if your recipients may. ``One must pay dearly for immortality: one has to die several times while alive.'' -- Nietzsche Laura Creighton ihnp4!hoptoad!laura utzoo!hoptoad!laura sun!hoptoad!laura