Philosophy Discussion Forums

Mercury wrote: ↑November 8th, 2022, 8:35 am All the bizarre theories mentioned are genuine implications of QM: multiverses, non-locality, quantum consciousness, holographic universe and so on. Which is why I suspect QM has something basic wrong. It's Mars doing loops in the sky; the theory is wrong. It has to be.

How can this be science? The evidence is there. The testing has been done, again and again. And yet you deny it? Any theory can be wrong, as all scientists know, but reality cannot. Reality is the reference against which all else is measured or judged. And so far, QM accounts for reality better than any other theory. This we must all accept, whether we like it or not, yes?

Mercury wrote: ↑November 8th, 2022, 12:08 am That's the idea that strikes me as potentially erroneous: "ultimately" - because it's baked into the language as an assumption that if we take something apart we naturally discover its constituent - fundamental building blocks. I have a sense that's incorrect; that beyond the atomic scale - as we keep dismantling particles, and sub-atomic particles, the existential 'object' is gone - such that we are breaking the down the very physics that defines the existential object - resulting in these weird effects, and what we end up with is not something fundamental, but just nothing.

It's way beyond me to prove it, but were that so, quantum mechanics would be "fundamentally" misconceived, and classical physics would be re-established as the core of scientific explanation. And I'd sleep better without the odd effects of QM projected onto macroscopic reality in a series of bizarre theories; multiverses, non-locality, quantum consciousness, holographic universe and so on, and on and on, lending credibility to anti-science crackpots and other subjectivists! The very fact that QM throws up so many wacky theories; or grand claims - as you say, suggests they've got something basic wrong!

Pattern-chaser wrote: ↑November 8th, 2022, 10:32 amOK, so how do you respond to the fact that QM is the most tested and the most successful theory in the history of science? You may not like it; you may yearn for the return of simpler theories; but this is wishful thinking, isn't it? QM works, and it works better than its predecessors. Even "anti-science crackpots and other subjectivists" know this, or at least many/most of them do. Where does that leave you?

I didn't take issue with the fact of quantum phenomena - I didn't say they don't occur, or that measurements don't show what they show. I argued that the theoretical understanding of these results is misconceived. Not least because QM keeps throwing up bizarre conceptions of reality; and they haven't been proven, have they? So where does that leave me? I guess that leaves me on the right side of Feynman's dictum: 'If you think you understand quantum mechanics, you don't understand quantum mechanics.'

value wrote: ↑November 6th, 2022, 1:40 pm

(2022) The Universe Is Not Locally Real, and the Physics Nobel Prize Winners Proved It
“Real,” meaning that objects have definite properties independent of observation—an apple can be red even when no one is looking; “local” means objects can only be influenced by their surroundings, and that any influence cannot travel faster than light. Investigations at the frontiers of quantum physics have found that these things cannot both be true. Instead, the evidence shows objects are not influenced solely by their surroundings and they may also lack definite properties prior to measurement.
https://www.scientificamerican.com/arti ... proved-it/

I've seen many discussions related to the question whether reality is really real. My experience has been that many users on this forum today are of the opinion that reality is really real and that consciousness is causally produced by 'the external world'.

A few days ago:

GE Morton wrote: ↑October 31st, 2022, 11:07 pmExplaining the existence of the "sensory facility per se" is precisely the purpose of "physicalist theory." It postulates an external world with mechanisms for producing conscious creatures. And it does a pretty good job of it.

The idea that reality is really real is based on a magical belief that underlays ontological realism. It is the belief that objective reality is ultimately something non-disputable within any context of thinking.

Well, first, all ontologists are "realists." They differ in what they take to be "real," in how they categorize the "real," and in which of those categories they take to be "fundamental," or primitive. Even Berkeley is a realist --- he just contends that only "ideas" are real. Physicalists, or materialists, on the other hand, can be either monists or dualists, holding either that only physical phenomena (matter, energy, and their interactions) are "real," or that, along with physical phenomena, "mental" phenomena are also real, though not fundamental, or primitive.

You also apparently misunderstand my views on these matters. But first we need to get clear on the meaning of the word "real," and define it in such a way that avoids the evasiveness and circularity in your "whether reality is really real" (above). Following Wittgenstein, we decide the meaning of a word in a natural language by observing how it is used in ordinary conversations. The term "real" is normally used to denote those things which are publicly observable, and which propositions about them are publicly confirmable. E.g., horses are real, unicorns are not; midgets are real, elfs are not; Prince Harry is real, Harry Potter is not, etc. But we would also say that, while unicorns and Harry Potter are not real we'd also say they are real fictional beasts or characters. So the denial that they are "real" in the first sense just means: they are not publicly observable physical entities; the issue is not whether Harry Potter and unicorns exist, but how they should be classified. Prince Harry is a real physical person, Harry Potter is a real fictional character. There are many other categories of "real" things as well. In short, we consider something to be "real," to exist, if it is something we can communicate about, exchange information about, or has some explanatory value. We just have to be careful not to imagine entities of one category as having properties belonging to entities in a different category.

The SA article you cited says "real" means, "objects have definite properties independent of observation—an apple can be red even when no one is looking." That is a bad example --- nothing has colors when no one is looking. Colors are strictly phenomenal effects occurring nowhere except in minds. What he should have said is, "objects emit or reflect light of various wavelengths when no one is looking." But it is correct in essence --- for scientists (and many philosophers) "real" means "exists independently of experience." The tree falls in the forest whether anyone observes it or not. Does it make a sound? Well, if you identify "sound" as atmospheric vibrations within a certain frequency range it does make a sound. If you instead consider "sound" to be the sensations we experience when detect those vibrations then no, it makes no sound if no one hears it.

I'm basically a Kantian. I take there to be 3 "first-order" categories of existents, of "real" things. Only one of them is "fundamental," or primitive, i.e., not reducible to the other two or to anything else:

1. Phenomena (the contents of experience), including percepts and their properties, feelings, moods, thoughts, ideas, memories, etc. This is the "fundamental" one, and the only one I'd call "ontologically real" (the other two are only "theoretically real"). Entities in this category are the only ones of whose existence we can be certain pre-theoretically, a priori, i.e., about which we can have no Cartesian doubt. If I see a tree I may wonder what is causing that percept, why I'm experiencing what I'm experiencing, but I can't doubt that I'm having the experience.

2. An external realm of existents (which may be singular rather than plural). This is Kant's noumena. This is a postulated realm which, though the postulate is created by minds and thus is dependent upon them, is independent of minds per the postulate. So if we accept the postulate we accept the existence of an independent external world of some sort. We are forced (so to speak) to this postulate because our minds are, per Kant, "programmed" to demand causes for effects --- that is what "explanation" is --- and hence we demand some cause(s) for the phenomena of experience, i.e., for our own existence. Since none is to be found within experience, we must assume some outside cause for it --- an external world of some sort.

3. Conceptual constructs. This one embraces everything else we take to be "real," to exist, everything from rocks and trees and cats and other people to electrons, quarks, and "quantum foam." These are entities we invent in order to usefully explain our experiences (what we observe, feel, remember, and so on), to provide causes for them ---a useful explanation being one which allows us to predict and manipulate those experiences, to control them to some extent, and to communicate about them. In its totality it amounts to a coherent conceptual model of the noumena, a "possible noumena," or of an aspect or portion of the noumena. Though we can never know just how accurately or completely this model represents the noumena, we allow it to "stand in" for the noumena as long as it and the entities it defines prove useful in predicting and controlling experience.

In short, except for phenomena, which are the only existents of which we can be apodicticly certain, "reality" is whatever we say it is --- provided what we say exists has some explanatory or communicative utility.

So to go back to your claim above: "The idea that reality is really real is based on a magical belief that underlays ontological realism. It is the belief that objective reality is ultimately something non-disputable within any context of thinking."

I have no idea where you think "magic" enters the picture. We have experiences, and we're driven to try to explain them, in order to be able to control them. To do so we postulate, theorize, an external world (or realm or agency) as the cause of them. Historically there have been two broad categories of these theories, "supernatural," or "god theories," and natural, or physical theories. The criteria for a successful theory is how much explanatory power it yields. Supernatural theories have very little; physical theories a great deal.

Regarding the experiments testing the Bell inequality: whether the universe is "locally real" (per the "independent of observers" definition of "real"), has no profound philosphical implications. If the idea that certain (theoretically defined) particles are "entangled" despite being separated by vast distances proves useful in explaining or controlling some experiences, then we're justified in revising our conceptual model of "reality" (the noumena) accordingly. It will just be the latest in a long series of revisions. The idea is certainly not an invitation to revert to a "supernatural" model.

Pattern-chaser wrote: ↑November 8th, 2022, 10:48 amHow can this be science? The evidence is there. The testing has been done, again and again. And yet you deny it? Any theory can be wrong, as all scientists know, but reality cannot. Reality is the reference against which all else is measured or judged. And so far, QM accounts for reality better than any other theory. This we must all accept, whether we like it or not, yes?

Quantum mechanics as such is nothing more than a (highly successful) mathematical recipe for making predictions that doesn't by and in itself provide a theory of physical reality. This is the reason why there is so much "interpretational" disagreement with regard to QM among physicists and philosophers of physics.

See the quotes in this previous post of mine: viewtopic.php?p=424143#p424143

Also:

QUOTE>
"Unlike Relativity, there is no agreement among physicists about how to understand quantum theory. Indeed, the very phrase 'quantum theory' is a misnomer: there is no such theory. Rather there is a mathematical formalism and some (quite effective) rules of thumb about how to use the formalism to make certain sorts of predictions. Here the difference between the ironworker and the philosopher of physics becomes acute. The ironworker (or the physicist in ironworker mode) doesn't particularly care about the nature of the physical reality: it is enough to calculate how various experiments should come out. The philosopher of physics cares about the underlying reality and attends to the predictions only insofar as they can serve as evidence for which account of the underlying reality is correct."

(Maudlin, Tim. Philosophy of Physics: Space and Time. Princeton, NJ: Princeton University Press, 2012. p. xiii)

"A physical theory should clearly and forthrightly address two fundamental questions: what there is, and what it does. The answer to the first question is provided by the ontology of the theory, and the answer to the second by its dynamics. The ontology should have a sharp mathematical description, and the dynamics should be implemented by precise equations describing how the ontology will, or might, evolve."

(Maudlin, Tim. Philosophy of Physics: Quantum Theory. Princeton, NJ: Princeton University Press, 2019. p. xi)

"The two pillars on which modern physics rests are the General Theory of Relativity and quantum theory, but the status of these two theoretical systems is completely different. General Relativity is, in its own terms, completely clear and precise. It presents a novel account of space-time structure that takes some application and effort to completely grasp, but what the theory says is unambiguous. The more one works with it, the clearer it becomes, and there are no great debates among General Relativists about how to understand it. (The only bit of unclarity occurs exactly where one has to represent the distribution of matter in the theory, using the stress-energy tensor. Einstein remarked that that part of his theory is “low grade wood,” while the part describing the space-time structure itself is “fine marble.”) In contrast, no consensus at all exists among physicists about how to understand quantum theory. There just is no precise, exact physical theory called “quantum theory” to be presented in these pages. Instead, there is raging controversy."

(Maudlin, Tim. Philosophy of Physics: Quantum Theory. Princeton, NJ: Princeton University Press, 2019. p. 2)

"If the problems with quantum theory are not “merely philosophical” but rather consist of the theory being unprofessionally vague and ambiguous as physics, why don’t the physics textbooks mention this? Much of the problem has been papered over by a misleading choice of terminology. A standard retort one might hear is this: Quantum mechanics as a physical theory is perfectly precise (after all, it has been used to make tremendously precise predictions!), but the interpretation of the theory is disputable. And, one might also hear, interpretation is a philosophical problem rather than a physical one. Physicists can renounce the desire to have any interpretation at all and just work with the theory. An interpretation, whatever it is, must be just an inessential luxury, like the heated seats in a car: It makes you feel more comfortable but plays no practical role in getting you from here to there.

This way of talking is misleading, because it does not correspond to what should be meant by a physical theory, or at least a fundamental physical theory. A physical theory should contain a physical ontology: What the theory postulates to exist as physically real. And it should also contain dynamics: laws (either deterministic or probabilistic) describing how these physically real entities behave. In a precise physical theory, both the ontology and the dynamics are represented in sharp mathematical terms. But it is exactly in this sense that the quantum-mechanical prediction-making recipe is not a physical theory. It does not specify what[5]physically exists and how it behaves, but rather gives a (slightly vague) procedure for making statistical predictions about the outcomes of experiments. And what are often called “alternative interpretations of quantum theory” are rather alternative precise physical theories with exactly defined physical ontologies and dynamics that (if true) would explain why the quantum recipe works as well as it does.

Not every physical theory makes any pretense to provide a precisely characterized fundamental ontology. A physical theory may be put forward with the explicit warning that it is merely an approximation, that what it presents without further analysis is, nonetheless, derivative, and emerges from some deeper theory that we do not yet have in hand. In such a case, there may be circumstances in which the lowest level ontology actually mentioned by the theory is not precisely characterized. In the rest of this book, I will treat the theories under discussion as presenting a fundamental ontology that is not taken to be further analyzable, unless I indicate otherwise.

A precisely defined physical theory, in this sense, would never use terms like “observation,” “measurement,” “system,” or “apparatus” in its fundamental postulates. It would instead say precisely what exists and how it behaves. If this description is correct, then the theory would account for the outcomes of all experiments, since experiments contain existing things that behave somehow. Applying such a physical theory to a laboratory situation would never require one to divide the laboratory up into “system” and “apparatus” or to make a judgment about whether an interaction should count as a measurement. Rather, the theory would postulate a physical description of the laboratory and use the dynamics to predict what the apparatus will (or might) do. Those predictions can then be compared to the data reported.

So far, then, we have distinguished three things: a physical theory, a recipe for making predictions, and the sort of data or phenomena that might be reported by an experimentalist. What is usually called “quantum theory” is a recipe or prescription, using some somewhat vague terms, for making predictions about data. If we are interested in the nature of the physical world, what we want is instead a theory—a precise articulation of what there is and how the physical world behaves, not just in the laboratory but at all places and times. The theory should be able to explain the success of the recipe and thereby also explain the phenomena."

(Maudlin, Tim. Philosophy of Physics: Quantum Theory. Princeton, NJ: Princeton University Press, 2019. pp. 4-6)

"What the quantum recipe does not resolve, what it does not even purport to address, is what the physical world is like such that the quantum recipe works so well. To answer this question, we need not more recipes, or better recipes, but something quite different from a recipe. We need a physical theory, a clear specification of what there is in the physical world and how it behaves. It is a plain fact about the world that the quantum recipe is an excellent predictive apparatus. That fact needs to be explained. And the recipe itself does not have the right form to serve as an explanation, because it is not a theory. The recipe itself does not say, for example, which parts of the mathematics used in the recipe represent physical features of the world and which do not."

(Maudlin, Tim. Philosophy of Physics: Quantum Theory. Princeton, NJ: Princeton University Press, 2019. p. 77)
<QUOTE

Tim Maudlin: What the Nobel prize gets wrong about quantum mechanics

"The 2022 Physics Nobel Prize is misunderstood even by the Nobel prize committee itself. What the work of John Clauser, Alain Aspect and Anton Zeilinger has shown, building on John Bell’s ideas, isn’t that quantum mechanics cannot be replaced by a deterministic, hidden variables theory. What it has shown is that quantum mechanics, as well as all of physics, is non-local. “Spooky action at a distance”, what Einstein had found disturbing about quantum mechanics, is real and emerging technologies depend on it, argues Tim Maudlin."

GE Morton wrote: ↑November 8th, 2022, 1:15 pmWell, first, all ontologists are "realists." They differ in what they take to be "real," in how they categorize the "real," and in which of those categories they take to be "fundamental," or primitive. Even Berkeley is a realist --- he just contends that only "ideas" are real. Physicalists, or materialists, on the other hand, can be either monists or dualists, holding either that only physical phenomena (matter, energy, and their interactions) are "real," or that, along with physical phenomena, "mental" phenomena are also real, though not fundamental, or primitive.

"Reality" = "the quality of being real or having an actual existence" (Oxford Dictionary of English)

Berkeley certainly considered spirits and their ideas to be real in the sense of having actual existence; but if to be real doesn't simply mean to exist (actually), but to exist perception-independently, then he doesn't consider ideas to be real in this narrow sense. As for spirits, Berkeley writes that "we have no ideas of spirits," which means that we cannot perceive them by having sense-ideas (sense-impressions) of them. To say that spiritual substances are imperceptible is not to say that they are inconceivable, since Berkeley does in fact have a concept(ion) of them.
Moreover, (bundles of) sense-ideas (sense-impressions) are what he calls "real things":

"The ideas imprinted on the senses by the Author of Nature are called real things."

(Berkeley, George. Principles of Human Knowledge. 1710. Part 1, §33)

GE Morton wrote: ↑November 8th, 2022, 1:15 pmYou also apparently misunderstand my views on these matters. But first we need to get clear on the meaning of the word "real," and define it in such a way that avoids the evasiveness and circularity in your "whether reality is really real" (above). Following Wittgenstein, we decide the meaning of a word in a natural language by observing how it is used in ordinary conversations. The term "real" is normally used to denote those things which are publicly observable, and which propositions about them are publicly confirmable.

I don't think "real" is normally used in this very narrow sense.

GE Morton wrote: ↑November 8th, 2022, 1:15 pm.g., horses are real, unicorns are not; midgets are real, elfs are not; Prince Harry is real, Harry Potter is not, etc. But we would also say that, while unicorns and Harry Potter are not real we'd also say they are real fictional beasts or characters. So the denial that they are "real" in the first sense just means: they are not publicly observable physical entities; the issue is not whether Harry Potter and unicorns exist, but how they should be classified. Prince Harry is a real physical person, Harry Potter is a real fictional character. There are many other categories of "real" things as well. In short, we consider something to be "real," to exist, if it is something we can communicate about, exchange information about, or has some explanatory value. We just have to be careful not to imagine entities of one category as having properties belonging to entities in a different category.

I think reality and fictionality are normally regarded as mutually exclusive, such that "real fictional character" is a contradiction in terms.

It certainly matters what exactly is meant by "realism" in this particular physical context:

Bell's Theorem > On "local realism"

Consul wrote: ↑November 8th, 2022, 3:25 pm It certainly matters what exactly is meant by "realism" in this particular physical context:

Bell's Theorem > On "local realism"

"The terminology of “local realistic theories” as the targets of experimental tests of Bell inequalities was introduced by Clauser and Shimony (1978), intended as a synonym for what Clauser and Horne (1974) called “objective local theories.” …For Clauser and Shimony realism is “a philosophical view according to which external reality is assumed to exist and have definite properties, whether or not they are observed by someone” (1978, 1883)."

Realism according to Clauser&Shimony:

1. There is an external reality. ("external" = "belonging or pertaining to the world of things or phenomena, considered as outside of the perceiving mind. external world: the totality of objects existing outside the conscious subject; the objective world; the 'non-ego'." – OED)
+
2. The things in external reality have objectively (observation- or measurement-independently) definite/determinate properties.

However, external realism as such doesn't entail objective definitism/determinism about properties.

Whether the concept of an indefinite/indeterminate property makes coherent ontological sense is another question. (I think it doesn't.)

Mercury wrote: ↑November 8th, 2022, 11:08 am ...QM keeps throwing up bizarre conceptions of reality; and they haven't been proven, have they?

I don't think you understand what science is, or how it works. Science has never proven anything. Science is not capable of proving anything. Science can only disprove theories. Theories that have not (yet) been disproven are tentatively accepted, until better ones emerge.

QM's "bizarre concepts" have been tested very thoroughly, and the testing has not (yet) disproven QM, or even shown that its more "bizarre" ideas are wrong. So it is, as I said, tentatively accepted until something better comes along.

Quoted from the video interview above:

"The reality of nonlocality has been settled, but how you implement it in a theory in a clear way has not at all been settled."
—Tim Maudlin

Mercury wrote: ↑November 8th, 2022, 11:08 am ...QM keeps throwing up bizarre conceptions of reality; and they haven't been proven, have they?

Pattern-chaser wrote: ↑November 9th, 2022, 9:45 amI don't think you understand what science is, or how it works. Science has never proven anything. Science is not capable of proving anything. Science can only disprove theories. Theories that have not (yet) been disproven are tentatively accepted, until better ones emerge.

QM's "bizarre concepts" have been tested very thoroughly, and the testing has not (yet) disproven QM, or even shown that its more "bizarre" ideas are wrong. So it is, as I said, tentatively accepted until something better comes along.

I don't think you understand that for religious and political reasons, Western philosophy has unreasonably emphasised subjectivism; while bashing science at every turn, and Popper's concept of science as falsification fits very comfortably within that tradition. If you adhere to Popper's theory of falsification, how can you ask:

"OK, so how do you respond to the fact that QM is the most tested and the most successful theory in the history of science?"

You clearly appeal to a concept of substantiation in support of QM; not falsification. Consequently, it's entirely reasonable for me to point out that the bizarre implications of QM understood as the search for a fundamental building block, are unsubstantiated. Which is to say "unproven" - something which we certainly would say were Western philosophy not infected with, and dying from a rabid religio-political anti-science disease!

Popper's other works include the Problem of Induction, and my particular favourite Enemies of an Open Society - in which he argues that science, because it's true, would be tyrannical were it recognised as truth. Taken altogether, Popper's works epitomise the religio-political assault upon science dating back to Descartes. Whereas, outside of this tradition, in science and in society - scientific proof is a much used and well understood term.

Almost everyone except philosophers are sophisticated enough to be able to appreciate that scientific proof is proof of the hypothesis specified in relation to the evidence offered - and does not imply some absolutist concept of truth with a capital T - but a valid condition within the specified range, open to revision in light of further evidence. Your failure to describe, and allude to such a qualified concept of proof is a demonstration of the one eyed myopia of the tradition from which you speak, because clearly, science does provide proof - and everyone knows that but you!

Mercury wrote: ↑November 9th, 2022, 10:32 am Almost everyone except philosophers are sophisticated enough to be able to appreciate that scientific proof is proof of the hypothesis specified in relation to the evidence offered - and does not imply some absolutist concept of truth with a capital T - but a valid condition within the specified range, open to revision in light of further evidence. Your failure to describe, and allude to such a qualified concept of proof is a demonstration of the one eyed myopia of the tradition from which you speak, because clearly, science does provide proof - and everyone knows that but you!

What you describe isn't proof, it's something more like confidence. This isn't just pedantry, it's much more important than quibbling over word-meaning. It's about how science functions. Science is an inductive discipline. It cannot be otherwise. It starts from observations or measurements — evidence — and tries to go from these specifics to the general: theories. The universe did not come with a rule book for humans, so this is the only possible way we could ever apprehend the functioning of the universe.

And because science is inductive, it cannot prove anything, but only disprove it by/with a contrary/contradictory example. This is fundamental to science, and therefore to an understanding of science. It matters, even to non-philosophers.

Pattern-chaser wrote: ↑November 9th, 2022, 10:45 amWhat you describe isn't proof, it's something more like confidence. This isn't just pedantry, it's much more important than quibbling over word-meaning. It's about how science functions. Science is an inductive discipline.

There is a deductive-nomological model of scientific explanation: https://plato.stanford.edu/entries/scie ... planation/

More information:

Action at a Distance in Quantum Mechanics: https://plato.stanford.edu/entries/qm-action-distance/

Mercury wrote: ↑November 9th, 2022, 10:32 am Almost everyone except philosophers are sophisticated enough to be able to appreciate that scientific proof is proof of the hypothesis specified in relation to the evidence offered - and does not imply some absolutist concept of truth with a capital T - but a valid condition within the specified range, open to revision in light of further evidence. Your failure to describe, and allude to such a qualified concept of proof is a demonstration of the one eyed myopia of the tradition from which you speak, because clearly, science does provide proof - and everyone knows that but you!

Pattern-chaser wrote: ↑November 9th, 2022, 10:45 amWhat you describe isn't proof, it's something more like confidence. This isn't just pedantry, it's much more important than quibbling over word-meaning. It's about how science functions. Science is an inductive discipline. It cannot be otherwise. It starts from observations or measurements — evidence — and tries to go from these specifics to the general: theories. The universe did not come with a rule book for humans, so this is the only possible way we could ever apprehend the functioning of the universe.

And because science is inductive, it cannot prove anything, but only disprove it by/with a contrary/contradictory example. This is fundamental to science, and therefore to an understanding of science. It matters, even to non-philosophers.

I disagree. It can be shown that "A causes B" with regard to experiment, verified by an independent observer. If you drop a rock it falls to the floor. Why? For the same reason that planets orbit the sun.

F=Gx(M/R^2)

F = force
G = gravitational constant
m = mass of object
r = distance between centers of the masses

If you say A does not cause B, then you imply that planets don't orbit the sun. Consequently, it's not inductive reasoning to say A causes B. When it is shown by experiment that the rock falls to the floor in accord with the same principle that explains how planets orbit the sun; that's proof - not merely that A causes B, but that reality is consistent in nature, and that generalised principles can be described, and employed to predict what will happen when the rock is dropped. It falls to the floor, everytime! Only a lunatic or a philosopher would think otherwise!