Davy_Jones

Don't the witchhunters in the thread have other witches to burn?

Oh, I know QM is a major headache to the realist. She extrapolates from quantum reality to macro-reality and gets caught up in all kinds of paradoxes and puzzles. The question I'm asking here, though, is: Why should the scientific antirealist (like almost everyone here it seems), if he is a commonsense realist too, squirm with questions about the reality of soccer balls (as you were doing, I think)? After all, the scientific antirealist doesn't believe all that quantum stuff is true. It's just a model. Seems to me the obvious answer he (the latter) should give is "Of course soccer balls are real. Why would you ask such a silly question?".

I'd like to direct the following to @Markus Hanke and @TheVat with regards your recent remarks on the difficulties that quantum weirdness imposes on ascribing reality to things like soccer balls and chimpanzees, say, while expressing my thanks once again for the stimulating input. Let's start with a refresher of Schrödinger and his fuzzy pussy, which no doubt everyone here is familiar with already, but with an emphasis on the realism-antirealism implications. Correct me if I butcher the physics or the history, gentlemen, as is quite likely. Schrödinger, along with Einstein, given their realist proclivities, were deeply dissatisfied with the dominant Copenhagen antirealist understanding of QM. Erwin, therefore, proposed his famous thought experiment in order to expose what he and Einstein took to be the inadequacy or incompleteness of the orthodox interpretation. A classic reductio ad absurdum. So what Schrödinger said was: "Hey guys, if what you're telling us is true, and that's all there is to the story, and we extrapolate from the micro to the macro realm, then we end up with absurd results . . . like a cat that is neither alive nor dead till someone takes a peek inside the box; a cat that, prior to being examined, exists in a superposition of . . . er, eigenvalues and wave functions or whatever." I'm not a physicist -- obviously! Feel free to substitute in the correct jargon. But note that dreadful word "true" in the first sentence. The scientific antirealist--Bohr, Heisenberg, and just about everyone here it seems--almost by definition is a person who does not think scientific theories, or at least those that posit unobservables, are true. The scientific antirealist, almost by definition, is a person who does not believe in the reality of unobservables like eigenvalues and wave functions and all the rest. As I've been told time and time again by the antirealistically inclined physicists here, "We don't deal with truth and reality. We are not even trying to generate true theories or describe (unobservable) reality. All we do is construct models which, to varying degrees, yield accurate desciptions of what can be observed. Our models are not to be taken as representations of reality; our models are not to be considered true or false. They are like maps, and a map cannot be true or false." And this is indeed a fairly standard instrumentalist-antirealist manifesto. It seems to me problems and paradoxes with extrapolating from the micro to the macro level only arise if one assumes a realist stance, as Schrödinger and Einstein did. From their perspective, if it's true in the quantum world then, by extrapolation, it must be true for the world tout court; true in the world as a whole . . . and the quantum fuzzy weirdness applies to trees as it does to quarks. But the antirealist (apparently just about everyone here) does not think it's true at the quantum level; it's just a model, not to be taken literally. The antirealist may not address questions about the reality of unobservable theoretical posits. It does not follow, however, that Niels Bohr, say, would deny reality to a very observable angry chimp banging on his windshield. Einstein, the realist, tossed and turned at night wondering whether the Moon ceases to have a determinate existence--a mind-independent existence--when no one is looking . . . as QM realistically interpreted implies (as far as I understand). Bohr, meanwhile, who did not interpret the theory realistically, presumably slept like a log. So my question for you guys is: Why should the reality of chimpanzees, rocks, soccer balls, and even Frank Sinatra cause you any sleepless nights . . . unless you believe quantum physics, or any science which posits unobservables, is literally true? What's keeping you awake? Shouldn't your position, the position of any scientific antirealist who is also a commonsense realist, be: "Of course the Moon and soccer balls and enraged chimpanzees are real" -- you "But what about quantum physics?" - some pest "Oh, that's just a model. You mustn't take these things literally. Goodnight!" -- you No doubt I'm missing something obvious here and making a fool of myself. But, hey, we live and learn. Your explanation would be greatly appreciated. I've assumed above from various comments in the thread that you are both more antirealistically inclined in these matters, at least with respect to QM. Forgive me if I'm misreading. If you're not antirealists yourselves, what do you think a typical antirealist would say? In the OP, I tried to explain the difference between (what I called) commonsense realism and scientific realism. One who assumes the latter position, denying the reality of quarks perhaps, does not necessarily hold to the former position and deny the reality of enraged chimpanzees.

I do wonder whether the human race will ever tire of hunting and burning witches. Re: (and I refer to the more malevolent elements in the thread, not you nice folks) the latest scandal from the quidnuncs around the scuttlebutt regarding myself imposing definitions on others Are we to believe now that I, perhaps with the help of a time machine, held a gun to the head of Einstein, Weinberg, Perrin, and all the rest, mercilessly forcing them to conform to my idiosyncratic definition (which I have never proposed in the first place) of reality? "Your obeisance to lexicographical tyranny or your life, sucker!" Let's suppose that what the Council of Grand Inquisitors says is correct, and we're all working with more-or-less different understandings of the terms truth and reality. It's not even all that implausible; intuitions do vary from person to person. The facts remain, however, that contra the opposition claims, there are scientists who are trying to describe reality as they understand the term ; there are scientists who speak of, who "deal with", truth and reality whatever these things mean to them. They said so! What next: they're all deluded liars? I could, of course, be quite wrong about all this. Wouldn't be the first time. Isn't it wonderful, though, that we live in an enlightened age where people can speak freely without fear of an auto-da-fé. Cough, cough.

The following is not particularly relevant to the OP, but if no one has any objections, I offer it for reflection (since the reality of gravity was touched upon). The question is this: Is it possible that we, or at least all those who currently believe in its reality, might one day come to believe that gravity is not real, that it does not exist? Newton was a cautious man. Though he did explicitly assert gravity really does exist, he shied away from "feigning any hypotheses" regarding its nature. What he did do, however, was to impute gravity as the cause--the common cause--of various observable effects (falling apples, motion of the planets and comets, tidal behavior, etc.). Then along came Einstein, also attributing gravity to be the common cause of the aforementioned effects, and a few others to boot (time dilation, etc.). Now, suppose one day we come to learn, or at least believe, that what we now attribute to a common cause (gravity) is in fact the result of multiple causes. What would we then say? (Those of you familiar with Hilary Putnam's celebrated "Twin Earth" thought experiment will see the parallels). One option would be to say: "Gravity is real. It is the collective name we give to a plurality of causes." Another option, however, would be to say . . . "Gravity doesn't exist. We were wrong" . . . and assign individual names to each of the multiple causes. I'm not suggesting this is likely (I've no idea how likely it is). What it does show, I think, is that the putative reality of gravity remains an open question. Would we call a substance on Twin Earth that is superficially indistinguishable from our water, but does not have the chemical formula H2O, water? Or would we give it another name? Intuitions differ.

Hmm, does not seem like a problem to me. No doubt there are difficulties with the concept; this doesn't appear to be one, though. Isn't this like saying, The coin has two sides: one heads and the other tails. Our concept of reality is a mess"? When one side of the planet is illuminated, the other is not. When it's summer in Canada, it's winter in Australia. Where's the problem? In the philosophy of language, they talk about indexicals (words such as "I", "now". "here". etc.), that is, certain statements are indexed according to the person, time, place, etc. of utterance. Therefore, taking indexicals into account, there is no contradiction between the statements "It's hot here", when uttered by yourself, and "It's cold here" when uttered simultaneously by me. Both can be true.

Oh, for crying out loud, Mr Eastwood. I was being . . . shall we say playful. And I think you know it. (And the next person who says "obtuse" gets shot. Seems to be a fave word around here.) Does it count that I feel 300 years old right now? What I said was "Then, thanks to the work of Perrin et al, all of a sudden atoms were real. And scientists said so explicitly." Whereas previously atoms had been regarded as "useful fictions" by the majority of relevant scientists, within a relatively short period they were being assigned ontological reality by the majority -- and said so explicitly. I did consider typing " . . . all of a sudden atoms were taken to be real" just to be super clear but withheld thinking it would be obvious. If it was less than clear, sorry; I am now clarifying. (If atoms are indeed real, then they were real at the time of the dinosaurs, real in 1900, real now, and will be real when we're all dead . . . unless you're a social constructivist. I'm not, and I highly doubt anyone else here is.) And why mention this at all? To provide further evidence, as if any more was needed, to refute various claims (see OP and the entire thread passim) to the effect that scientists/physicists do not try to describe reality, scientists do not deal with reality, hard-nosed scientists do not talk about metaphysical airy-fairy will-o-the-wisps such as truth and reality. What current scientists, including those here, happen to feel about the reality of atoms does nothing to vitiate the refutation. All it takes is one flying bird. I have not provided a definition of real, in this thread or any other. See above. I have given no definition of real. But yes, echoing your own thoughts, I'm sincerely pleased to have this opportunity to learn from so many knowledgable people, including yourself. The seemingly insatiable nastiness and character defamation, though, (which the mods incomprehensibly do nothing about) from certain members has me very close to cashing in my chips. The reason is that, in a debate over the the truth of the claim "birds don't fly", pointing out a few penguins and cassowaries (as my opponents have been doing) carries little weight. Pointing to just one soaring eagle, on the other hand, serves to refute the claim immediately. I've pointed out a veritable flock of seagulls . . . to little avail it seems. (Now apply that, mutatis mutandis, to the claims we actually are debating -- see my will-o-the-wisp comments a few paragraphs above) For the third time, I have offered no definition of real. What I have done is refute the claims just mentioned. It is not true that there are no scientists (cf. "there are no birds that fly") that are trying to describe reality, aiming for truth, and all the rest. They said so themselves! How many times does Mr Sinatra have to sing to falsify "Ole Blue Eyes never sang a song in his life"? Peace and love to all.

Obtuse? Bad faith? You have no idea how hard I've been biting my tongue here . . . continually being insulted and "corrected" by (certain - some have been very nice) people who clearly haven't the faintest idea what they are talking about. Call me fat, bald, ugly. I couldn't care less. Please do not insult my integrity, though. I do care about that. Thank you. Now, is this your proof for the existence of gravity? "People fall to the ground from 10th floor windows. Therefore gravity exists"? Observe, I will now prove the existence of phlogiston using identical reasoning: "Stuff burns. Therefore phlogiston exists" QED Philosophy of science was never so easy. Have you seen gravity? What does it look like?

The above was in response to beecee's "Scientific models and theories by definition, do not set out to reveal whatever truth and/or reality that we can be aware of. " Once again, with all due respect to all involved, I find remarks like these very puzzling. Let's talk Copernicus and Galileo . . . Is it your position that Copernicus, when he proposed his heliocentric model/theory, was not telling us this is the way the solar system really is? If so, how do you know this? What evidence do you have to support this view? (My understanding is that precisely the opposite obtained, but I'd have to read up on it all again before committing.) The case with Galileo is even clearer: That's exactly what he was saying, i.e. The Copernican model/theory is (a representation of) the way things really are . . . and that's why, or at least one of the reasons why, he got into so much trouble. The Church was quite clear on this: You may promote the Copernican model, Signor Galileo, just so long as it is construed instrumentally, just so long as it is understood to be a mathematical calculating device, just so long as you don't go around telling people it is literally true. Galileo, being the scientific realist par excellence that he was, found himself unable to bite his tongue. And the rest is history . . .

Better keep your voice down. You can get into a lot of trouble for saying things like that around here. The others will explain to you what "real" really means to a scientist.

I've heard Isaac Newton say it. "Hitherto I have not been able to discover the cause of those properties of gravity from phenomena, and I frame no hypotheses... And to us it is enough that gravity does really exist, and act according to the laws which we have explained, and abundantly serves to account for all the motions of the celestial bodies, and of our sea." Yet another case of a scientist, a fairly accomplished one at that, making existential claims about unobservable reality.

Those members who continue to insist--despite voluminous evidence presented to the contrary--that scientists don't talk about metaphysical nonsense like reality and truth (or if they do, it's not to be taken too seriously), science "doesn't deal" in such things, only philosophers lie awake contemplating such silliness, etc., may wish to examine the following article on physicist Jean Baptiste Perrin, as well as his speech upon acceptance of the Nobel Prize. (see link). By the way, you may also have noticed that the only person here who has presented any actual substantive evidence, in the form of actual quotes from actual scientists, and not simply personal anecdote (roughly "Scientists don't talk like that!! Coz I say so!!"), is myself. Strange days indeed! https://www.nobelprize.org/prizes/physics/1926/perrin/facts/ Highlights include: Introduction . . . 1. "Jean Perrin maintained that if molecules were real, particles blended into a liquid should not all sink to the bottom but should distribute themselves throughout the liquid." And now Perrin speaking himself . . . 2. "These brilliant successes tell us, otherwise, nothing about the absolute weights of the atoms. If they all became at the same time a thousand times smaller, a milliard times smaller, infinitesimal in the mathematical sense of the word, with matter becoming again continuous at each reduction, our chemical laws and our formulae would be unchanged, and the idea of the atom, then driven back infinitely far beyond all experimental reach, would lose its interest and its reality." 3. "Such a collection of agreements between the various pieces of evidence according to which the molecular structure is translated to the scale of our observations, creates a certitude at least equal to that which we attribute to the principles of thermodynamics. The objective reality of molecules and atoms which was doubted twenty years ago, can today be accepted as a principle the consequences of which can always be proved." 4. 'Even whilst evidence continued to accumulate on the still disputed atomic reality, a start was made to penetrate the interior structure of these atoms, a research in which Rutherford and Bohr obtained marvellous results, as we know.'

Oh, I'm not sure that's true, sir. These things can be a big deal. Take, for example, the reification of atoms around the turn of the 20th century. Prior to then, atoms had been widely regarded as simply a "useful fiction" . . . much as other members in this thread speak about current theoretical posits. Then, thanks to the work of Perrin et al, all of a sudden atoms were real. And scientists said so explicitly.

I got a rap on the knuckles earlier, various accusations of dishonesty, and enough downvotes to sink the Titanic for--supposedly--putting words in other people's mouths. (I don't think I was). Better watch yer step, Clint. It's a rough town. I really don't care all that much about whether scientific realism or antirealism is the more appropriate stance. I just find it interesting, that's all. But insult Mr Sinatra and ya better bring a gun, punk. (just having fun )

Re above Let's grant everything you just said is true. If these observables are taken to be real, but not the unobservables (conveniently ignoring what prof Lincoln explicitly states -- cough, cough), science nonetheless "deals with" reality, right? It deals with these observables that you speak of. It is describing observable reality. Edit: Er, what is "iirc" ? Belief, eh? Well, to believe a given proposition is, by definition, to believe that it is true, and to believe in something is to believe that it exists. If (at least some) scientists do indeed believe in dark matter and similar unobservable creepie-crawlies, then they are not only dealing with observable reality, but (what they take to be) a real unobservable reality (pardon the pleonasm) too. And that's known as scientific realism . . . a position that everyone here seems to think exists only in my overactive imagination. One cannot claim--on pain of inconsistency--that he believes in something, but does not think it is real. Unless, of course, you're just having fun (cf. "I don't believe in ghosts . . . but they scare me!").