I have of course put in my own overall rebuttal to ES’s reply to SB’s challenge, but I feel a commentary on points will also be helpful. U/D, Feb 20: I have taken up the general LNC issue, here.)
Such is best done using a full post, so, I clip from EL’s own post. My comments will be on numbered arrow points, and will be OLIVE GREEN:
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[EL:] On Uncommon Descent, Barry Arrington asks:
[BA:] Let’s clear up this law of noncontradiction issue between StephenB and eigenstate once and for all. StephenB asks eigenstate: “Can the planet Jupiter exist and not exist at the same time in the same sense? That’s a “yes or no” question eigenstate. How do you answer it?
[EL:] For some reason, Eigenstate’s response has gone astray, so here it is, as cross-posted elsewhere:
Eigenstate:
Theoretically, yes.
1 –> ES, in effect here agrees that A AND NOT_A can both be true in the same sense and time. What immediately follows is what I pointed out in my own comment early this morning:
Do you not see the chaos of self-referential absurdities that stem from denial of the principle of non-contradiction, that if one asserts A AND NOT-A in the same sense and time, then one ends with as a logical consequence that any and every assertion follows as having truth value, True?
That is, by swallowing the premise of a core self-contradiction in our reasoning, we reduce ourselves to increasingly losing the ability to discern the true from the false, save where we unconsciously revert to the old fashioned way of thinking.
Let’s call it straight: reduction to absurdity by self referential incoherence, presented as wisdom. “Professing themselves to be wise . . . ”
And, no, it is not just a matter of imposing arbitrary rules of manipulating symbols and calling them axioms.
The law of non-contradiction was a matter of reality and the human condition of experience of having to live with it, long before it was ever reduced to symbols. Indeed, it is a case of self-evident truth.
Truth, that, in light of our experience of the world and understanding, we see as not just what happens to be so but could have been otherwise, but instead what must be so, on pain of obvious and blatant in-your-face absurdities and contradictions leading to radical chaos of incoherence.
I assure you, that the self same ones appealing to quantum double slit exercises, entanglement, wave functions and probabilities, etc, would never dream of walking out into a busy highway on the assumption that the cars and trucks zipping by were and were not there in the same sense and time.
They cannot live with the pretty arguments on the ground, a sure sign that something is drastically wrong.
1a –> Let me add, overnight, a look at the quantum
world through the eyes of the Dr Quantum video on entanglement, quantum superposition of what we used to call matter waves, and notice the evident reality of the smeared out wave that interacts with say injection of an observing apparatus [so an “observed” double slit is NOT equivalent to the original case!] and the wavicle challenge:
https://www.youtube.com/watch?v=TMzh0gTTJI8
1b –> In short the issue here is that if we superpose A and B, we get C, not A and NOT-A or the like:
A + B –> C
In practice, the probabilities are so vanishingly small it’s indistinguishable from no.
2 –> ES here indicates his intended “out,” quantum mechanics where outcomes are perceived to include superpositions that may collapse like Schrodinger’s poor cat held hostage to a radioactive trigger that may/may not release a vial of cyanide. Until we open up, we know not the outcome, and the set of possibilities is said to be superposed.
3 –> This brings up one side, that observability is what scientific investigations are about, so we cannot meaningfully discuss the unobservable or that which cannot be inferred from observation. (That may, BTW, have some very interesting implications for speculations on deep past origins theories.)
4 –> It is worth recording Schroedinger’s words:
One can even set up quite ridiculous cases [for the Copenhagen view]. A cat is penned up in a steel chamber, along with the following device (which must be secured against direct interference by the cat): in a Geiger counter, there is a tiny bit of radioactive substance, so small that perhaps in the course of the hour, one of the atoms decays, but also, with equal probability, perhaps none; if it happens, the counter tube discharges, and through a relay releases a hammer that shatters a small flask of hydrocyanic acid. If one has left this entire system to itself for an hour, one would say that the cat still lives if meanwhile no atom has decayed. The psi-function of the entire system would express this by having in it the living and dead cat (pardon the expression) mixed or smeared out in equal parts. It is typical of these cases that an indeterminacy originally restricted to the atomic domain becomes transformed into macroscopic indeterminacy, which can then be resolved by direct observation. That prevents us from so naively accepting as valid a “blurred model” for representing reality. In itself, it would not embody anything unclear or contradictory. There is a difference between a shaky or out-of-focus photograph and a snapshot of clouds and fog banks.
4 –> Yup, back in 1935, Schroedinger was objecting by posing an intended reductio based on the first principle of right reason known as the law of non-contradiction, and that in a communication to Einstein. Schroedinger certainly would not have seen this issue as a dismissal of that law of reasoning. (And remember, a lot of modern mathematics is established based on reductio arguments, aka proof by contradiction.)
5 –> So, what is going on here is that those who reject non-contradiction are reading back into quantum mechanics to find a justification.
6 –> Let’s pause to see what Wiki does by way of summarising other interpretations. Here, Bohr:
one of the main scientists associated with the Copenhagen interpretation, Niels Bohr, never had in mind the observer-induced collapse of the wave function, so that Schrödinger’s Cat did not pose any riddle to him. The cat would be either dead or alive long before the box is opened by a conscious observer.[6] Analysis of an actual experiment found that measurement alone (for example by a Geiger counter) is sufficient to collapse a quantum wave function before there is any conscious observation of the measurement.[7] The view that the “observation” is taken when a particle from the nucleus hits the detector can be developed into objective collapse theories. In contrast, the many worlds approach denies that collapse ever occurs.
7 –> So, we have a many worlds model that in effect has an exploding number of universes, at each quantum event. My own response to such, is where does the energy come from, and the information to branch the world like this? never mind, in no one universe do we have any blended is/is not state, and that we have many worlds in which, collectively, all possibilities are actualised on this model does not undo LNC.
8 –> The same sort of pattern can be traced through the various theories. For instance, on the relational view:
The cat can be considered an observer of the apparatus; meanwhile, the experimenter can be considered another observer of the system in the box (the cat plus the apparatus). Before the box is opened, the cat, by nature of it being alive or dead, has information about the state of the apparatus (the atom has either decayed or not decayed); but the experimenter does not have information about the state of the box contents. In this way, the two observers simultaneously have different accounts of the situation: To the cat, the wavefunction of the apparatus has appeared to “collapse”; to the experimenter, the contents of the box appear to be in superposition. Not until the box is opened, and both observers have the same information about what happened, do both system states appear to “collapse” into the same definite result, a cat that is either alive or dead.
9 –> So, clearly, quantum physics does not provide a slam dunk case that establishes a YES AND NO world.
10 –> And, worse, we see something more, we have the way the very equations of quantum mechanics work, i.e the way physicists have to work with the equations, So, as I noted:
Without these relationships [the principles of right reason] , Mathematics becomes impossible, and the whole project of physics, including quantum physics, collapses.
Kindly, explain to me, what happens to [the way we have to interpret symbols as having a definitive meaning, and expressions as having definitive rules and relationships]:
E_k [photoelectron] = h*f – phi
Where also, E-photon = h*f
And where also, save f exceeds a certain level, no photoemission is possible.
(Onlookers, I choose this case as it is the case that established quantum mechanics, and it is the case that was a key factor in Einstein’s Nobel Prize.)
. . . if there are no rules of mathematical reasoning, physical reasoning and objective observation and measurement, in light of reality, like this.
Scale matters; superposition is fragile with respect to other elements in the system that force a classical resolution.
11 –> We are now beginning to follow a red herring, and are dealing with a strawman (which is a type of red herring), as it has not been shown that superposition definitively imposes a rejection of LNC.
Recent experiments have provided experimental verification that macroscale objects can be put in superposition (see here):
Quote
But although the rules of quantum mechanics seem to apply at small scales, nobody has seen evidence of them on a large scale, where outside influences can more easily destroy fragile quantum states. “No one has shown to date that if you take a big object, with trillions of atoms in it, that quantum mechanics applies to its motion,” Cleland says.
The “paddle” object in this experiment was just 30 micrometers long. But that’s freaking HUGE compared to the Planck length. Jupiter is just so many orders of magnitude bigger than that, that the prospects for superposition in that case become ONLY theoretical. Too many resolving influences make it statistically impossible.
12 –> The question is begged here, that once quantum state superpostion is introduced, LNC has been dismissed. Sorry, not so.
The linked article describing the experimental evidence for QM weirdness “scaling up” includes this comment from a physicist at the U of Oregon:
Quote
“It’s wonderful,” says Hailin Wang, a physicist at the University of Oregon in Eugene who has been working on a rival technique for putting an oscillator into the ground state. The work shows that the laws of quantum mechanics hold up as expected on a large scale. “It’s good for physics for sure,” Wang says.
So if trillions of atoms can be put into a quantum state, why don’t we see double-decker buses simultaneously stopping and going? Cleland says he believes size does matter: the larger an object, the easier it is for outside forces to disrupt its quantum state.
(emphasis mine)
Those wacky physicists, I tell ya.
13 –> We are now well off topic, and are pummelling away at a strawman; now resorting to ridicule, the issue being lost sight of in the laugh.
On an LNC-related note, this from the same article:
Quote
Next, the researchers put the quantum circuit into a superposition of ‘push’ and ‘don’t push’, and connected it to the paddle. Through a series of careful measurements, they were able to show that the paddle was both vibrating and not vibrating simultaneously.
(emphasis mine)
14 –> This they may say; that, they have not actually shown, by virtue of the very fact that once we observe a superposed system, we see it in — surprise [NOT] — a definite state.
15 –> Since this was an object that is of classical size [about that of a living cell], did they snap and show a video of the thing both vibrating and not vibrating? Could they? As Maverick Philospher observed on being challenged with the same case:
[MP:] The salient point is that, on the ‘many worlds’ interpretation of QM there is no violation of LNC not even on the micro-level let alone on the macro-level. Given that there is no one settled interpretation of QM accepted by all physicists, the case against LNC at either level is bound to be weak.
[Q:] This is very tricky stuff, but I think it is the paddle, a macro object that we can directly observe under other conditions, that is now in the superposition state of moving and not moving. We in fact have put it into this state. The paddle is not some ding an sich, but an ordinary object that can transition from existing “normally” in one state or its opposite to existing at once in both contradictory states. In principle any macro-object could be reduced to such a quantum ground state but we just can’t physically do so.
[MP:] I am afraid that you are not making sense. You have already granted that the paddle that we see with the naked eye cannot be seen by the naked eye to be both moving and not moving, But now you are saying that that very visible paddle — and not some invisible micro-constituents of it — has been put by the experimental apparatus into a state in which it is both moving and not moving. This implies that one and the same visible paddle is both (moving & not moving) and not (moving & not moving). Which is is higher -order contradiction.
Are you saying that there are two paddles? Then they can’t both be visible.
Furthermore, if you say, as you do above, following the Copenhagen interpretation, that observation of the paddle forces it into one state or the other, then cannot also say that that very same visible paddle is in both states.
I am afraid that the science journalist’s report on the Cleland experiment has delivered us into a realm of rank gibberish.
16 –> What was observed was a voltage or something like that indicating that the system was vibrating. It evidently took a value intermediate between the expected for the two states. So, if vibrating produces a voltage, etc, and there was a voltage, of whatever size, was the object “not-vibrating and vibrating,” or was it instead vibrating in a way that was intermediate between the two expected values? (And wouldn’t that be worth exploring? As in, are we observing superposed states; what would be the common-sense answer in any other situation?)
Sound familiar, StephenB (and Barry, if you’ve been reading our exchange)? I will note here that champignon’s comment on this being best viewed as a Law of the Excluded Middle issue is a point well taken. But that notwithstanding, you have QM weirdness in the real world ostensibly misbehaving against our propositional logic. “Vibrating” and “Not Vibrating” in the same sense, for the same object at the same time.
17 –> This is indeed how it was reported, but the empirical evidence suggests something else: that the object was vibrating, as opposed to vibrating and not vibrating. (The value of vibration — frequency or amplitude etc — may not be as “expected,” but that is a different matter. NOT-VIBRATING means, no oscillations, of any frequency or waveform. Still. And, plainly, “still” this object was most definitely not.)
Here’s another example from a similar experiment (link),
18 –> Here is the crucial matter:
. . . The experiment combines two possibilities, known as a quantum superposition, for the direction of the flow of electric current: clockwise around the loop or counterclockwise.
The researchers measured an energy difference between the two states of the loop, a sign the current was a quantum superposition and not simply flipping directions.
Just as the cat is neither alive nor dead but a ghostly mix of the two possibilities, the current flows neither clockwise nor counterclockwise, but is a mix of the two possibilities.
19 –> Again, a current was measured, and evidently its value was intermediate between expected values. This was seen as consistent with a superposed state, but that is not logically equivalent to the system was not having a current, or that the current was BOTH one way, AND the other way. There was a current, just not the current that would be expected from either of the ideal states.
20 –> This suggests that we may observe superposed physical states under some interesting conditions, but not that such a state is based on a combination of contradictory possibilities that are logically mutually exclusive. Alive and dead are not to be compared to vibration possibilities or current levels etc.
21 –> It is, after all, a commonplace of waves that they may superpose, and indeed an interference pattern is a classic case in point, yielding results that may go beyond one way or another or be intermediate or even a null, at a node. Alive and dead are not in the same boat.
22 –> So, I think rather the results you have cited should be reported as: superposed states are observed under special conditions.
where Dr. Anthony Leggett of U of Illinois, Champaign, Urbana weighs in on a solar system body — not Jupiter but the moon (the moon was the example Einstein initiated these questions with: “does the moon exist if no one is looking at it?” :
Quote
For Dr. Leggett, quantum mechanics at the macroscopic level is still uncertain — and troubling. “It may bother me even more now,” Dr. Leggett said. “I’m interested in the possibility that quantum mechanics, at some stage, may be wrong.”
A few physicists have devised so-called macrorealistic theories to resolve the ambiguities of quantum mechanics. “What you get in quantum mechanics is not what you see,” said Dr. Philip Pearle, a professor of physics at Hamilton College in Clinton, N.Y. “Schrödinger felt this acutely. He himself felt something with quantum mechanics was wrong.”
Dr. Pearle and colleagues in Italy propose to add a term to Schrödinger’s equation that, in effect, constantly jiggles the fabric of the universe. Atomic-scale objects only jiggle a little and thus remain a blur, which preserves the predictions of quantum mechanics. Larger objects, like people or the Moon, jiggle more and quickly fall into a definite here and there, which corresponds to everyday experience.
(emphasis mine)
23 –> Again, we see something here: the proposal of a state of affairs that is possible and in that case the apparent contradiction vanishes into a resolution. That is actually highly significant, on the logic involved:
We have items x1, x2, . . . xn, a set X, that are thought to stand in mutual contradiction
However, if we augment X by adding some term y1, which is a possible state of affairs, the elements stand in coherence
Here, the logical suggestion is that we are actually seeing superposition states.
In strict logic, then, x1, x2, . . . xn are not contradictory.
Barry, if you’ve read my earlier responses to StephenB on this, you will recognize the same ideas quoted here in my answers. Jupiter has a virtually zero statistical basis for avoiding decoherence, hence it will ALWAYS be there in the full, classical (non-superposition) sense.
24 –> Which is still irrelevant. All you have said is that on quantum mechanics, Jupiter is a composite quantum object, of macroscopic scale. Such objects will asymptotically approach the classic result.
25 –> But ever since Copenhagen, the correspondence principle was imposed as a means to assuring this, and used in the theory as a component. A quantum result that does not reduce to the classic case on sufficient expansion is invalid.
26 –> And the point is that since such classic results are empirically well grounded, if the quantum model did not so reduce, it would cut across observation and show itself to be in error.
27 –> We could have saved ourselves the circuitous detour and simply have said that Jupiter is made up of atoms which are quantum objects. However, it is on such a scale that the quantum result will approximate so closely as to make no practical difference to the classic one. If Jupiter exists at the classical level of observability as a planet, the quantum result is that we would observe it as existing.
28 –> On pain of discrediting itself as contradicting observed reality.
Lastly, this, regarding the LNC-problematic nature of this second expirement:
Quote
The experiment combines two possibilities, known as a quantum superposition, for the direction of the flow of electric current: clockwise around the loop or counterclockwise.
The researchers measured an energy difference between the two states of the loop, a sign the current was a quantum superposition and not simply flipping directions.
Just as the cat is neither alive nor dead but a ghostly mix of the two possibilities, the current flows neither clockwise nor counterclockwise, but is a mix of the two possibilities.
(my emphasis)
29 –> Already addressed. If we are observing actual states that are the superposition of the quantal possibilities, that is an actual observation, we are not seeing this and not this. And, superposed vibrations and waves, electrical or mechanical, etc, are not at all the same as the notion of a cat being simultaneously alive and dead in superposition. Of course Shroedinger’s thought mechanism was used to highlight that this is a crucial difference to be resolved.
Note that per superposition, this is not simply a matter of a “bi-directional current”. This is two otherwise exclusive one-way directions happening at the same time, exclusive states superimposed:
Quote
A measurement always gives one of the two possible answers, clockwise or counterclockwise, never a zero cancellation.
30 –> And, the observed state is: “the current flows neither clockwise nor counterclockwise, but is a mix of the two possibilities.” That is, more precisely we see a current somewhere along the spectrum from all one way and all the other; a blended state similar I suppose to the delocalised electrons forming the ring orbital in the benzine ring. If that is happening along a probability distribution per stochastic effects, the odds of seeing a special value like zero would be practically zero. (I know, I know, that is suspiciously like the design inference, but that is pretty much what I was told when I asked an accountant on the possibility of a profit and loss account netting to zero: never going to happen, said he.)
31 –> In short this sort of thing is actually most likely a longstanding commonplace quantum effect, e.g. the benzine ring orbit is sometimes spoken of as a blend of several possible bonds, often with percentages given. We are not at all locked up to there being a case of two contradictory alternatives being both simultaneously true.
Glad to have the opportunity to settle this once and for all! Statistically, it will never happen for Jupiter, but it remains a theoretical possibility.
32 –> What, that Jupiter simultaneously exists and does not exist in the same sense and place and time? On a case where the quantum result has to reduce to what we observe at macro level in any case or it will be empirically invalidated?
It’s the same as wondering if I could fairly shuffle and deal a 52 card deck and deal the cards out, producing the same exact card order as the first shuffle a billion times in row. In theory, it cannot be eliminated as a possibility. As a practical matter, the odds are insdistinguishable from zero.
33 –> Utterly irrelevant. The card shuffles, if they happen, happen; we do not have an intermediate state between “yes the all but impossible event happens and no, the all but impossible event does not happen.” If you think so, show us the video.
34 –> Just so. Jupiter exists as a planet or it does not exist as a planet, a specific object orbiting our sun. There is no intermediate state between the two. If Jupiter is there, we have a large gas giant planet. If not, we do not have the planet there at all. Tell us, what would a superposition of the two look like?
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In short, what we have is a case where we may be seeing the sort of superposed states that in organic chemistry are described as hybrid orbitals. What ES has not done is to show us a good reason to believe that Jupiter the planet is and is not, in the same sense and time. yes, we are seeing some statements in articles that make me wonder if people are thinking through what they are asserting. They seems to be missing out that just maybe, they are observing superpositions of ideal quantum states; what they have actually outright said.
Why should a superposed outcome be seen as a combination of something being in case A AND case NOT-A at the same time? Is it not in case C, where case C is a combination of contributions from parent cases A and B? In crude terms is not a child distinct from both parents?
I can find no good reason to infer that such a superposition would be equivalent to something existing and not existing at the same time, or something simultaneously vibrating and not vibrating, or a circuit having a current that is simultaneously flowing clock- and anticlock- wise. END
F/N: Since this is meant to supplement a discussion thread already in progress, comments will not be allowed. Kindly go to the main thread.
F/N 2, Feb 14: Perhaps inevitably, paraconsistent logics have been injected into the debates. I suggest the briefing here at IEP, will be helpful. Suffice to say that, in the reasoning about this, we can see the classical “laws of thought” at work implicitly everywhere we turn; just as with the classic case of the physicists’ chalk marks on chalk boards (the traditional tools of theoretical physics). Maybe, too, this clip from the in-draft NCSTS unit 2 section on building a worldview can help take the “mystery” and “suspect-ness” out of those classic first principles of right reason:
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>>. . . though it is quite unfashionable to seriously say such nowadays (an indictment of our times . . .), to try to deny the classic three basic principles of right reason — the law of identity, that of non-contradiction, and that of the excluded middle — inevitably ends up in absurdity.
For, to think at all, we must be able to distinguish things (or else all would be confusion and chaos), and these laws immediately follow from that first act of thought.
A diagram showing the world split into two distinct labelled parts, A and NOT-A, will help us see how naturally this happens:
If at a given moment we distinctly identify and label some thing, A — say, a bright red ball on a table — we mark a mental border-line and also necessarily identify NOT-A as “the rest of the World.” We thus have a definite separation of the World into two parts, and it immediately and undeniably holds that:
(a) the part labelled A will be A (symbolically, [A => A] = 1),
(b) A will not be the same as NOT-A ( [A AND NOT-A] = 0); and
(c) there is no third option to being A or NOT-A ( [A OR NOT-A] = 1).
So, we see how naturally the laws of (a) identity, (b) non-contradiction (or, non-confusion!), and (c) the excluded middle swing into action. This naturalness also extends to the world of statements that assert that something is true or false, as we may see from Aristotle’s classic remark in his Metaphysics 1011b (loading the 1933 English translation):
. . . if it is impossible at the same time to affirm and deny a thing truly, it is also impossible for contraries to apply to a thing at the same time; either both must apply in a modified sense, or one in a modified sense and the other absolutely.
Nor indeed can there be any intermediate between contrary statements, but of one thing we must either assert or deny one thing, whatever it may be. This will be plain if we first define truth and falsehood. To say that what is is not, or that what is not is, is false; but to say that what is is, and what is not is not, is true; and therefore also he who says that a thing is or is not will say either what is true or what is false. [Emphases added]
So, we can state the laws in more or less traditional terms:
[a] A thing, A, is what it is (the law of identity);
[b] A thing, A, cannot at once be and not-be (the law of non-contradiction);
[c] A thing, A, is or it is not, but not both or neither (the law of the excluded middle).
For a fire to begin or to continue, we need (1) fuel, (2) heat, (3) an oxidiser [usually oxygen] and (4) an un- interfered- with heat-generating chain reaction mechanism. (For, Halon fire extinguishers work by breaking up the chain reaction.) Each of the four factors is necessary for, and the set of four are jointly sufficient to begin and sustain a fire. We thus see four contributory factors, each of which is necessary [knock it out and you block or kill the fire], and together they are sufficient for the fire.
We thus see the principle of cause and effect. That is,
[d] if something has a beginning or may cease from being — i.e. it is contingent — it has a cause.
Common-sense rationality, decision-making and science alike are founded on this principle of right reason: if an event happens, why — and, how? If something begins or ceases to exist, why and how? If something is sustained in existence, what factors contribute to, promote or constrain that effect or process, how? The answers to these questions are causes.
Without the reality behind the concept of cause the very idea of laws of nature would make no sense: events would happen anywhere, anytime, with no intelligible reason or constraint.
As a direct result, neither rationality nor responsibility would be possible; all would be a confused, unintelligible, unpredictable, uncontrollable chaos. Also, since it often comes up, yes: a necessary causal factor is a causal factor — if there is no fuel, the car cannot go because there is no energy source for the engine. Similarly, without an unstable nucleus or particle, there can be no radioactive decay and without a photon of sufficient energy, there can be no photo-electric emission of electrons: that is, contrary to a common error, quantum mechanical events or effects, strictly speaking, are not cause-less.
(By the way, the concept of a miracle — something out of the ordinary that is a sign that points to a cause beyond the natural order — in fact depends on there being such a general order in the world. In an unintelligible chaos, there can be no extra-ordinary signposts, as nothing will be ordinary or regular!)
However, there is a subtle facet to this, one that brings out the other side of the principle of sufficient reason. Namely, that there is a possible class of being that does not have a beginning, and cannot go out of existence; such are self-sufficient, have no external necessary causal factors, and as such cannot be blocked from existing. And it is commonly held that once there is a serious candidate to be such a necessary being, if the candidate is not contradictory in itself [i.e. if it is not impossible], it will be actual.
Or, we could arrive at effectively the same point another way, one which brings out what it means to be a serious candidate to be a necessary being:
If a thing does not exist it is either that it could, but just doesn’t happen to exist, or that it cannot exist because it is a conceptual contradiction, such as square circles, or round triangles and so on. Therefore, if it does exist, it is either that it exists contingently or that it is not contingent but exists necessarily (that is it could not fail to exist without contradiction). [–> The truth reported in “2 + 3 = 5” is a simple case in point; it could not fail without self-contradiction.] These are the four most basic modes of being and cannot be denied . . . the four modes are the basic logical deductions about the nature of existence.
That is, since there is no external necessary causal factor, such a being — if it is so — will exist without a beginning, and cannot cease from existing as one cannot “switch off” a sustaining external factor. Another possibility of course is that such a being is impossible: it cannot be so as there is the sort of contradiction involved in being a proposed square circle. So, we have candidates to be necessary beings that may not be possible on pain of contradiction, or else that may not be impossible, equally on pain of contradiction.
In addition, since matter as we know it is contingent, such a being will not be material. The likely candidates are: abstract, necessarily true propositions and an eternal mind, often brought together by suggesting that such truths are held in such a mind.
Strange thoughts, perhaps, but not absurd ones.
So also, if we live in a cosmos that (as the cosmologists tell us) seems — on the cumulative balance of evidence — to have had a beginning, then it too is credibly caused. The sheer undeniable actuality of our cosmos then points to the principle that from a genuine nothing — not matter, not energy, not space, not time, not mind etc. — nothing will come. So then, if we can see things that credibly have had a beginning or may come to an end; in a cosmos of like character, we reasonably and even confidently infer that a necessary being is the ultimate, root-cause of our world; even through suggestions such as a multiverse (which would simply multiply the contingent beings) . . . >>
_____________
In short these principles are not arbitrary, nor are they question-begging. Indeed, trying to deny them tends to put would-be dismissive deniers into logical hot water; starting with implicitly using what they would deny in attempting to make a clear statement of what they are trying to say For if we accept A AND NOT-A, the meaningfulness and specificity of what we say is one of the first things to evaporate.