Reg Prescott

Once again, all I can say is I'm not competent to answer that. Bas van Fraassen (and others) write a lot about models -- the so-called semantic view of theories, I believe -- but quite frankly, it gets pretty technical and goes over my head. I don't know if a model can be true or false, I don't even know if scientific theories, or some of them, are best regarded as models. As always. several posters have simply asserted this, but like everything else in the philosophy of science, it's hotly contested. But what we can all agree on, I presume, is that whatever we take our theories to be, we hope that they will generate true observational consequences or predictions. A perfect theory would generate only true predictions, given the proper background assumptions. Therefore, the claim that science has nothing to do with truth seems misguided to say the least. Re : true and false are models - sorry, don't understand that As for the classification of Boolean algebra : sorry again, pal, ain't got the foggiest. Is there a logician in the house?

Sorry, friend, I don't know enough about these things to comment. It would be nice if I had a little back-up here. It feels like me against the world The good news is, though, this seems to be my first successful foray into the quote function. It's not rocket science, after all, eh?

Mornin' all. It's a brand new day and time to do some more thunkin... Now, first of all, let's be quite honest; as if we didn't have enough ghouls here already, but this new spook - "scientific truth" - was introduced to the party as a rather desperate attempt by Strange to escape from a corner he'd painted himself into (see posts 78 and 80). (I say this not to be mean to Strange or anyone else; I say it because it's TRUE ) Now, here's the problem: if, as you claim (incorrectly, if I may be so impertinent), that you regard your theories as nothing more than models, or calculating devices, or instruments, then the term "truth" is misapplied. An instrument or a tool is surely not the kind of beast that can be true or false. We might describe one screwdriver as better than another, or we might append the epithet useful to a power drill, or say that my Samsung Galaxy works better than your hunk of trash, but normal people (dunno 'bout you guys though ) do not go around calling these things true or more truth-like. It struck me later that the concept you've been calling "scientific truth" is that which certain philosophers of science refer to as "empirical adequacy". (note: adequacy is quite a different beast from truth; "adequate" is more akin to good enough). Might we all, please, switch to using the term empirical adequacy instead of scientific truth from now on to avoid confusion between the two "truth"s? Thanks if that's cool. Now, your question for today, boys and girls, is : imagine a case where you have two theories which postulate completely different entities and mechanisms, yet both are perfectly consistent with all available evidence; nay, let's go further and suppose they're consistent with all possible evidence. No observation or experiment can ever tell between them. We can all agree that both theories are empirically adequate to the same degree (i.e. they both work equally well), but how many of you would be willing to bite the bullet and concede that both theories are true? (in the normal sense of true - i.e. corresponds with what is the case in reality) And who among you would prefer to say "We have two theories that are empirically indistinguishable but logically incompatible. One may be true and the other false. Or both may be false. But as a matter of pure logic, both cannot possibly be true." P.S. And all idealists are kindly invited to leave. The room's getting cold. . . . P.P.S. @ - "Oh , I forgot, You don't reply to my questions since they are too difficult." -Studiot Yeah, ask some easier questions, dammit

Great question about the hole, swansont. Lemme think about that. Dang, no sleep tonight then @ - "It seems to me that this implies two different meanings for "true" and the problem here is that you keep hopping back and forth between them, whenever it's convenient for you." (blue font to match your lovely suit) Au contraire, old chap. That, I must dispute. It's PRECISELY the risk the others run though -- with their bizarre dichotomy between "scientific truth" and, er, good ole fashioned regular truth.

Strange: "Of course. There are many cases where we have multiple theories which are "true" in this sense. For example, Newtonian gravity and GR. Or classical electromagnetism and quantum theory." The calculations both theories yield may be similar. But surely the theory is more than just the calculations it yields? The stories Newton and Einstein tell us vis-a-vis the nature of space, time, gravity, mass, etc are very different, aren't they? Given that, would you still hold that both theories are true? @ Klaynos : "If they make equally accurate predictions when compared to the observations you have no choice but to consider then equally good theories." But that wasn't what I asked, naughty boy. Tsk Tsk. I asked do you consider them to be both true? Anyway, it's bedtime here. It's been fun, guys. And I don't feel quite so hated today Peace and love! Oh and lotsa truth too

Swansont - "So your claim was that most scientists do not accept abstractions — it's all about "truth" (as opposed to "fiction"). Meaning you did say such a thing." Yes, I suspect if we surveyed scientists across the board (not just physics - stop being so physics-centric) we'd find that most of them are engaged in trying to portray reality as accurately as possible - whether they know it or not and whether they'll admit or not. The nice folks here are already coming round to my way of thinking. Gimme a lil more time And re : "And yet you are insisting on things despite your lack of knowledge. Isn't it possible that you're wrong, owing to your admitted ignorance?" Is it possible I'm wrong? You betcha, baby.

a question for ajb... you said: "Based on what I have read and listened to, by 'true' he does indeed mean that the idea of evolution matches the observations very well. In that sense evolution is 'true'." If this is what you mean by "true", then if you had two theories that matched the observations equally well, you'd have to say "They're both true". Right? Er, are you truly cool with that, dude? I'm not knocking it; just wondering if you're willing to accept the ...um, potentially unpalatable implications of your own unorthodox definition.

Klaynos : "Those complications, such as how you counted them, do brown dwarfs count, what are the limitations if your optical system matter though. Do no I don't think you can say that statement is true or false. Again this is an observation. Testability is fundamental else there's no point." Oh yeah? How about if I were to claim the answer is....um, one? Or how about if I were to claim the Earth is 5000 years old? C'mon now. You'd say "That's just WRONG, dumbass" Strange - "Congratulations on discovering the Quote button though" Er, obviously still requires a little work. Is there a tutorial or something somewhere?

Just to add a little more to my post before the this.... The scientific realist holds that while we may not enjoy certainty in our theories, we can at least claim a certain justification -- we have good reasons for believing that our theories approximate a true description of reality. And he might add with a hint of pride "...which is more than you nutters can claim"

Well, tell that please to Richard Dawkins who keeps insisting that evolution is TRUE.

Well, the point of all this is -- see Einstein quote again -- a scientific realist (with regard to whatever given theory) holds that things out there are a certain way independently of our minds. He maintains we are limited in what we can know about it; we might never be able to enjoy certainty (which certain posters in the thread repeatedly confuse with "truth"; the latter is a semantic notion, the former is an epistemic one -- accepting that one cannot enjoy certainty does not preclude one from being a scientific realist) in our theories, but we can at least enjoy some degree of justification in our beliefs -- by testing and confirming our theories as best we can. Given a God's-eye view we could produce theories that are true simpliciter. Denied that, we can at least try to produce theories which approximate truth. Or in the case of Einstein's watch analogy.... things in there are a certain way....etc, etc

I did say "avoid unnecessary complications. Ok, try this then... Say, there is a certain number of marbles in an urn. We do not, or cannot, know what the answer is (we're denied access for whatever reasons). Does this imply there is no determinate number of marbles in the urn just because we can't know it? The number of marbles in the urn is a question of metaphysics (reality). Whether we can know the number is a question of epistemology (our beliefs and knowledge). The two mustn't be confused.

Klaynos -- "How have you tested the water for impurities? Can you prove that what the dog is drinking is 100% H2O? If you cannot then how is that statement "true"? " A key question indeed, and one that has been causing all kinds of confusion throughout the thread. Take a statement such as: "The number of stars is odd" Presumably this statement is either true or false (ignoring unnecessary complications). Would you agree? Now, whether we can KNOW (or prove it) is an entirely different question, an epistemic question. Do you see the difference? Now do you see the problem with your statement above? Presumably the statement "The dog is drinking pure H20" is either true or false. Agreed? Whether we can KNOW this is an entirely different matter. or if this is more clear.... the fact that we do not, or cannot, know which value (T or F) the statement should be assigned does not imply that it has no determinate value. Do you see?

ajb -- "In other sciences it may not be so clear cut as this, while in mathematics the aim is to try to produce only true statements" Well, why wouldn't you want that for yourself in science? Even if you can't always attain it, don't you think you should AIM for it? Or do you think scientists should deliberately aim for a few false statements here and there? * raises another eyebrow *

@ Klaynos I'm simply using the term "true" in what I take to be its everyday usage (what philosophers refer to as "the correspondence theory of truth") A statement is true if it corresponds to actual states of affairs in the world. E.g. The statement "The dog is drinking water" is true if and only if the dog is drinking water. The statement "All copper conducts electricity" is true if and only if it is indeed the case that all copper conducts electricity. The statement "Humans evolved from apes (or apelike creatures or whatever)" is true if and only if this statement corresponds with what is the case in reality. It's not the only theory of truth out there, but I assume it's the one we all use on a daily basis. Or do you have another in mind? So do you believe science should AIM TO produce statements/hypotheses/theories of that type? Or AIM TO produce statements that are false?

Strange - "Whereas, the scientific definition of "truth" is more like "consistent with what we observe" (and, for realists, this will be extended to "consistent with reality"; But you've been telling us over and over again science has (almost) nothing to do with truth. A change of heart?

@ - "Evolution is consistent with what we observe" So you think it might be true? Or have a chance of being true? Or somehow truth-like? (Or even entirely untrue?) If not, why are scientists invariably appalled when our religious loonie friends refuse to accept it?

@ Klaynos Well, no one ever gave me an answer to this (post 52)... "How, then, may I ask would our other members reply to a wayward Creationist, say, who wandered in and expressed his firmly held belief that evolutionary theory was a load of crap? How many among you, in all honesty, would tell him, "Don't worry, pal. Our evolutionary theory has nothing to do with truth. You're better to think of it as a model, or a useful fiction, that we use as a calculating device to .... erm, cure baldness (or whatever). It has nothing at all to do with the way things really are out there." "

@ Strange Your last post is another case of gross misrepresentation. I honestly don't understand why the staff don't do anything about this. I can't even be bothered pointing out your misrepresentations, or trying to get through to you anymore, but I'll be happy to explain to any impartial staff member who contacts me. Finally, re your "This means you are like someone who read a book on first aid telling a bunch of surgeons what they are doing wrong." Or perhaps you're like a football player who believes ONLY football players themselves could possibly know anything or have anything worthwhile to say about football. P.S. Just as the religious loonies claim too -- the "You're not one of us. What could you know about it?" syndrome.

@ swantson -- "According to your stated position these aren't abstractions; they must be real, and that there are many scientists who think so." Utter nonsense. I've never said such a thing. It's pointless to even continue. Apparently you're a physicist. I'm not. If you were to talk heavy duty physics to me, it would probably go right over my head. Unfortunately what's happening here is that we're discussing philosophy of science (something I do know a little about) and the reverse is happening -- you (and others) are consistently failing to understand me. All I can do is post a link and perhaps some readers will take a little time read it. http://plato.stanford.edu/entries/scientific-realism/

. . . In the thread so far, I seem to have made myself very unpopular by challenging what I take to be absurd claims such as the following: (i) "Remember, science is not about "truth" but about models that work;" (post # 5) (ii) "Science has (almost) nothing to do with "truth", whatever that is. For that you want religion." (post # 10) (iii) "I don't remember hearing any scientists say anything other than theories are just attempts to model reality, not attempts to uncover the truth. Given the way that theories are constantly being modified in the light of new evidence, it would be very short sighted for anyone to say "this theory is true"." (post # 31) (iv) "Theories are not "true" or "false", they are better or worse models." (post # 55) In the Youtube clip I'll post below (assuming the link works), Neil deGrasse Tyson tells us "The good thing about science is that it's true whether or not you believe in it." Well, Prof Tyson's claim is patently as absurd as the claim that science has (almost) nothing to do with truth. I'm just wondering if my assailants in this thread would administer the same treatment to Prof Tyson as they have to myself. After all, if one of you is right, the other is hopelessly wrong. But what worries me is that, under normal circumstances, they'd join in the thunderous applause with the studio audience in the background. Yes, you might say it's just a chat show. Let's not get our kinickers in a twist. Fair enough. But then again, we don't like it when the religious nutters advance absurd, exaggerated, unjustifiable, or even demonstrably false claims. Why, then, do we not only condone a high profile scientist doing so, but cheer too?

It's frustrating that I'm being misunderstood and misrepresented over and over again, particulary by the two most recent posters. I will not even address Strange anymore; he's done it once too often (why don't the staff do something about this?) And how did "idealists" get into the discussion. Whoever mentioned idealism? Just briefly, in response to swansont's latest post: @ - "Explain in terms of what they actually do. If theories are tied in with truth (as you have described it), how are these realists testing that theories are truly describing reality? Take any example I have given of things that I say are abstractions." Sorry, I can't even make sense of this (test an abstraction for reality?). Anyway, let's just say my answer is "I've no idea". Why don't you explain? Thanks. @ - "It also nicely captures the idea that he was not a realist. He's saying there's no way to know if your model is reality. You've successfully debunked part of your own argument." I don't think I have debunked myself; Einstein's remarks seem perfectly consistent with a realist position to me. He even says explicitly "In our endeavour to understand reality ... ", and again, "He will never be able to compare his picture with the real mechanism ..." What more evidence could you possibly need for his realist stance? He's speaking (or at least this is how I see it) as man who holds that there is just one way things are out there independent of ourselves, our theories are an attempt to capture that reality (they are not mere abstractions or useful fictions, which is the attitude adopted by the instrumentalist), and while we might enjoy some degree of epistemic justification that we've got things right, we can never be "quite sure". Deepest apologies to Mr Einstein if I'm misreprenting you. Interpreting other people's words is a hazardous business. @ - "They're getting the behavior right. No surprise there, since it's what people have been saying all along. You've failed to make your point. You have to establish that they are getting something else right, too." No, you misrepresent me again. Please stop doing this. I didn't claim they're getting something (or something else) right; I expressed my suspicion that they'd like to believe they're getting something right. Whether they are or not is another question. I made no claim that they're getting something right, so I'm under no obligation to establish it. Perhaps the elliptical form of my sentence misled you. Apologies if so. Let me be more clear. Here's the sentence again (clarification in blue): "I suspect -- and you guys may confirm or disconfirm -- that most scientists would like to believe that even if they're not capturing the absolute truth in their best theories (which would be a very hard claim to defend), (they would like to believe that) they're at least making an approximation to a true description of reality - (they would like to believe that) they're getting SOMETHING right." - Me, post 62 P.S. I believe much of the confusion in this thread arises from some posters failing to appreciate that scientific realism and instrumentalism are attitudes that one can adopt to any given theory as one pleases, on a case by case basis. It is not necessarily an en bloc position taken across the board with respect to all theories. One might, for example, assume an instrumentalist attitude toward quantum theory (i.e. holding that what we have is a useful tool, but it should not be understood as describing how things really are down there), while at once adopting a realist attitude to tectonic plate theory in geology.

I'm not at all sure that it is possible to tell. Again, many people much more capable than myself have written on this, and if there's a last word to be said, it sure ain't gonna come from yours truly. I suspect -- and you guys may confirm or disconfirm -- that most scientists would like to believe that even if they're not capturing the absolute truth in their best theories (which would be a very hard claim to defend), they're at least making an approximation to a true description of reality - they're getting SOMETHING right. See my comments above on evolutionary theory, for example (post 52), or consider, perhaps, the case of geologists and plate tectonics. I find it very hard to believe that all geologists regard these beasts as nothing more than abstractions or useful fictions. What do you think? I suppose, furthermore, that many/most scientists would like to believe that successor theories have a greater truth content than predecessor theories. But here the philosophical waters get pretty deep. No one so far, to my knowledge at least, has been able to provide a satisfactory characterization of the notion of verisimilitude, or truth-likeness. Popper, for one, tried and failed. One thing, though, that is pretty much universally conceded these days, I believe, is that no amount of testing or evidence or confirmation can ever prove a theory, in the logical sense. A theory is never entailed by data/evidence, again in the logical sense. Or as they like to say, theories are underdetermined by data. Here's a quote from Einstein that captures this nicely: Physical concepts are free creations of the human mind, and are not, however it may seem, uniquely determined by the external world. In our endeavour to understand reality we are somewhat like a man trying to understand the mechanism of a closed watch. He sees the face and the moving hands, even hears it ticking, but he has no way of opening the case. If he is ingenious he may form some picture of the mechanism which could be responsible for all the things he observes, but he may never be quite sure his picture is the only one which could explain his observations. He will never be able to compare his picture with the real mechanism and he cannot even imagine the possibility of the meaning of such a comparison."

@ swansont : "How do you evaluate a theory, then? Or discard one? How do you test for the "reality" of a theory, other than by evaluating whether it makes correct predictions of experiments?" As I've explained, I'm not here -- I wouldn't pretend -- to make normative judgements on what scientists ought to do. Many people have written on these matters though, of course -- and they offer wildly divergent advice. In an earlier age, inductivists like Bacon, Newton, and Mill would have told you roughly, I suspect, that theories are somehow derived from data; testing therefore is largely redundant. Descartes might have appealed to deduction from first principles. Whewell would invoke somethink akin to the hypothetico-deductive model. Popper would insist that theories can never be confirmed to any degree (since induction is incurably invalid. How many scientists would be willing to bite THAT bullet?); they can only be deductively falsified. Kuhn would mention paradigms and explain the reasons he believes lead to scientists abandoning one in favor of another. Lakatos would speak of scientific research programmes. And bad-boy Feyerabend would tell us there is no universal method or rationality in either the discovery or the confirmation/testing of theories - anything goes! And as we see, everyone in this thread has their own views on the matter too. @ Klaynos Sorry, I'm not deliberating ignoring anyone. A lot has been said, and just writing as much as I have has been very time consuming. Would you mind repeating which point you'd like addressed, please? And don't hold your breath that I'll have anything intelligent to say on it.

@ swansont again : you said -- "The issue is whether theories represent realities, and I have given examples of well-established physics where abstractions are used. Do you have a rebuttal to that or not? I'm sorry, but this is another misrepresentation of events. You originally made the claim (post 39) that "Physics describes how things behave, not what they are." I took umbrage. Perhaps what you claim is true in some cases. But it's certainly not true in all cases. And I've posted evidence that I believe refutes your claim.