The "Stage Theory of Theories" - Cause for Concern?

[axocanth]

It just means an explanation of a system in terms of a components particular function. "The kidneys keep the blood clean by filtering out cellular waste products" is a functional explanation. So is "the heart acts as a pump to circulate the blood." Not having seen the video, I can't say much about its use of the term. Functional explanations often become settled science - highly unlikely that we will abandon the heart-as-pump explanation and assert that its primary function is a rhythm section for bands that can't afford a drummer.

(my red emphasis)


Very droll, Mr Vat. This is way off topic, of course, but if you remember, way back around the time the Beatles were wooing America, we had a discussion on your site about Jerry Fodor's critique of natural selection theory, expatiated in his book "What Darwin Got Wrong".

The thrust of his critique is that natural selection theory requires a distinction between that which is selected for (e.g. the heart pumping blood as contributing to fitness), and that which is merely selected, the so-called "free rider" (e.g. the thump-thump noises of the heart irrelevant to fitness). And evolutionary biologists do indeed note such a distinction.

Fodor argues that, although it's certainly a distinction we can make, it's not a distinction that Mother Nature herself can make. Hence, the theory is false.

Needless to say, Fodor was put through the mill, hung drawn and quartered, the inevitable fate of any Darwinian naysayer.

The more I've thought about his critique over the years though -- and it is extremely subtle -- the more convinced I am that he's absolutely right.

Anyway, right or wrong, the man is quite brilliant, a delight to read. Equally obvious is that the vast majority of his critics simply did not get what he was saying.

 

[axocanth]

Consider, for example, this bizarre claim from a science defender found in the Intelligent Design Redux thread (post #973):


"Science isn't about knowing or proving. Science is about observing the evidence and developing an explanation that best meets that evidence. We have a mountain of evidence of incremental evolution over millions of years leading to divergent species." - DaveC426913


So, in a stunning volte-face from Neil deGrasse Tyson's "science is true", we are now told that science is not in the business of producing knowledge.

And with friends of science like that, who needs enemies?

 

[DaveC426913]

Now bring this back and apply it to the word theory. How is it different?

Ignoring this doesn't make it go away.

This whole thread is about the equivocation of one word.

 

[axocanth]

P.S. to my last post above, and with my longer post at the bottom of the previous page in mind.

And if you do decide that science is producing knowledge -- as every sane person does -- then you can't bury your head in the sand and pretend that scientists make no truth claims. Knowledge is, by definition, true.

 

[axocanth]

I think it's important for scientists and science communicators, when speaking to general audiences, to try to convey that scientific progress isn't just a matter of coming up with imaginative descriptions of how the natural world might work. It's also about hypothesis testing, evidence gathering and comparing theory to experiment. Biologists don't believe in the Theory of Evolution because it sounds like a good "just so" story; they believe in it because mountains of evidence tend to confirm the usefulness of the theory. Creationists, of course, find themselves in the tricky position of not only lacking confirmation of their own "theory", but actively having to deny or ignore the significant body of evidence that tends to refute it. Selling the tale that science is really just guesswork and storytelling seeks to put science on an approximately even playing field with the tales the Creationists tell. If Creationists (or other pseudoscientists) can manage to do that, then the choice between something like the Theory of Evolution and Creationism is reduced to a matter of aesthetic preference.

Now compare with Dave's "Science isn't about knowing" (see above), and entertain the following fictional exchange:


"So is there any reason for us to believe this tale you're telling you're telling us about evolution?" - Creationist

"Don't look at me, dude. Science isn't in the business of generating knowledge. It's a nice explanation though. Helluva story, eh?" - Dave


To be quite clear, it's not my purpose to embarrass or ridicule anyone here. But anyone who takes it upon themselves to "educate" others about science -- as Dave is doing against his ID rivals -- and making such preposterous claims, has some radical rethinking to do.

STOT advocates, of course, takes matters to the other ludicrous extreme: All scientific theories are probably true, and thus constitute knowledge..

 

[DaveC426913]

"Don't look at me, dude. Science isn't in the business of generating knowledge. It's a nice explanation though. Helluva story, eh?" - Dave

I'll thank you to not put words in my mouth. Especially in quote marks.

Particularly since I have been nothing but civil and respectful to you, even in our disagreements.

 

[James R]

axocanth:

Thanks for starting an interesting conversation. I think this discussion is certainly worth having.

Rather than responding to every point you've made, I'm going to concentrate on the points where I disagree with you or otherwise have something to add to what you've written. You can probably safely assume that I'm broadly in agreement with you in regards to the parts I don't comment on. You can be sure that I'll let you know if something comes up that seriously bothers me.

I think this is to mischaracterize the situation in all kinds of ways. First, in cases of wild guessing, we tend not to use the word "theory". If, for example, I laid a pack of cards in front of you and said "50 bucks if you can guess the top card", it would be very strange indeed to reply "My theory is that the top card is the king of diamonds." Do you agree?

Perhaps. But on the other hand, consider an example where two people are flipping a coin and trying to guess the result of the next flip. It seems quite natural to say something like "Well, the coin has come up tails on the last four flips. So my theory is that on the next flip, the coin will turn up heads."

And that can only be a wild guess, if the coin is unbiased etc.

I think it's unlikely that any scientist with a grade school understanding of probability theory would use the word "theory" there, but I don't think it would be hard to find similar examples of that usage among non-scientists.

A theory, I think, tends to be something we can offer some kind of rationale (cf. evidence) for.

That immediately imports a scientific way of thinking - or at least a rational way of thinking about things. But people are often irrational and unscientific in the way they talk and (fail to) reason, and that irrationality tends to manifest more in some circumstances than others.

Your car mechanic most likely thinks in a very rational "scientific" way when he evaluates whether your carburetor is fubar. But that is not guaranteed to carry over to when he's placing a bet on a coin flip or whether red or black will come up on the roulette wheel.

What is a theory anyway? Perhaps the first thing that comes to mind is that a theory -- regardless of whose theory -- is something that takes us beyond direct observation.

Theories often make predictions about future events. Scientific theories aim to allow us to predict the outcomes of particular observations or experiments.

Typical scientific theories, on the other hand, posit entities, processes, and mechanisms that no one has ever seen, and indeed may never see, things that are simply inaccessible to our human sensory apparatus.

Inaccessible in a direct sense, certainly. But we humans tend to augment our direct senses with various instruments and detectors.

And as other members have noted with due modestly, it is quite likely that even our best theories today will be consigned to tomorrow's history books as little more than a curiosity.

The history of science tends to suggest otherwise. While it is true that theories sometimes need to be thrown away completely, it is often the case that current theories are found to be correct in some appropriate approximation of a new and improved theory. We still guide our interplanetary spacecraft using Newton's law of gravity, because it works well enough, even though we have found that it's only an approximation of the "more correct" theory of General Relativity in an appropriate limit.

 

[James R]

Check out also the Youtube gods I mentioned in the OP. Know Forrest Valkai? He says this kind of thing routinely.

Certainly, Forrest Valkai doesn't get everything right. But from what I've seen of him, he is a good science communicator. Also, he's quite young. He'll get better.

Have you ever seen The Atheist Experience on youtube, or heard it in podcast form? If not, I recommend that you watch an episode or two, to see what Forrest (and the other hosts) have to deal with, week in and week out. The level of ignorance of science - even the grade school stuff - from certain callers beggars belief. In that environment, just about any education about what it means to think critically, or about how science is done or what it has found, has to be a net positive.

 

[James R]

What we can say is this: Anyone telling the public -- whether directly or implicitly (usually the case) -- that we have good reason to believe that any and every scientific theory is true is courting disaster.

Usually, though, these science communicators are not talking to the general public about the latest arguments scientists who are working at the bleeding edge of research are having about competing "theories". Far more often, communications to general audiences are about scientific ideas that are tried and tested - i.e. capital-T Theories that have earned that capital T because we have very good reasons to believe they are true. [*More on truth, as it applies to theories, to come, below.]

A rapturous audience proceeds to applaud what may be the most preposterous claim of the century; a flat earth pales in comparison.

But does it, really? The flat earth "theory" is far more popular than you might imagine, which suggests that the more pressing problem might be more basic than your concern about the nuances of the word "theory", at least from a science educator's point of view.

But knowledge -- by definition -- entails truth, and what good is an explanation if it is not true?

Well, there are alternative measures of "goodness". For instance, we could ask whether an explanation is useful, even if it's not "true". But this is a whole other can of worms.

And presumably no scientist would endorse: "We have lots of weird and wonderful explanations . . . oh, and none of them are true.".

You might be surprised. Scientific realism isn't the only possible philosophical stance on this stuff, even though it might be the most common one among scientists.

Meanwhile, how else are we to understand "highly confirmed" or "well substantiated" if not as likely to be true?

Well, we can ask questions like "Does this theory make accurate predictions, when we compare its predictions against real-world experiments and observations?"

If the answer to that is "yes", then it appears that the theory might be useful, regardless of whether it is True.

Is it even possible to judge, in advance of testing, whether a new scientific theory is likely to be true? How do you propose that we should go about deciding that?

"This theory is highly confirmed and likely to be false?" Surely not.

Newtonian gravity, to repeat an example, is highly confirmed. But we also know that it's false, in a technical sense. Or maybe it's mostly true. Or true in a lot of circumstances. Or true enough.

We can really get into the philosophical weeds once we start talking about what is and isn't true.

The T-word has to be confronted sooner or later, unless of course one adopts an instrumentalist position whereby the terms true/false simply do not apply.

As I've got older, I've personally become more partial to an instrumentalist way of thinking about scientific theories. I'm not completely committed to it. Maybe I don't even understand it well enough to make a well informed choice, but from what I know of it, it sounds sensible enough. But this, again, is really a topic for a different thread, I think.

And as soon as you do that, on pain of inconsistency or incoherence you'd better stop talking about theories explaining anything or scientific theories being falsifiable. Only that to which the terms "true" and "false" apply stands a chance of being falsified.

That might depend on how you want to define falsification. On its face, the word "falsify" means "to prove something false", so there's that. But in science we often (always?) can't prove theories to be true. Which was Popper's point, I suppose...

Reverberating through the thread are hints, here and there, that Joe Sixpack is just a layman after all, we can't hit him with science in all its esoteric profundity, we have to dumb these things down a bit for him. Science educators are doing their best.

In one respect, there's nothing special about science in this regard. If a car mechanic hits me with details of the internal workings of my carburetor in all its esoteric profundity, I'm probably going to glaze over in a similar way to a non-expert audience hearing about the applications of tensor calculus in general relativity.

In other words, when talking to any general audience (composed of non-experts, for the main part), one almost inevitably has to dumb these things down - whatever they are. One tries to communicate the essentials - or the interesting bits - and one tends not to spend one's limited time diving into the weeds of "what exactly do we mean when we say 'theory'?" or "Let me tell you about all the details of the engine into which the carburetor is installed."

And when Mr Sixpack discovers that he's been told a load of bollocks, he's liable to be less than impressed. Who wouldn't be?

Often, education is a matter of building up a complex story. We start with simple things. We often skip over complicated details, counterexamples to the general principles and matters of nuance, at first. Once the student has grasped the essentials, then we often revise: "Previously, we told you this, but it turns out that's not quite true in every circumstance, because you also have to consider [insert more advanced idea]."

Students, for the most part, are usually forgiving of being told a simpler "load of bollocks" initially, provided that it is clearly flagged that the load of bollocks is not the whole story, or is a general rule with some exceptions, or is a useful building block on the road to a more complete understanding.

It's not a matter of telling lies to the student. It is matter of pointing out that you, as an expert, are only telling part of a bigger story, in a way that they are ready to digest.

I felt the same way when I discovered that canonical Gospels were not written by the people I'd been led to believe they were.

The problem there is that it is very seldom flagged that the Gospels have a far more dubious origin story than the one that is typically implied when students are first introduced to them. More worryingly, those particular stories are seldom taught in a context of critical thinking. Rather, they tend to be taught as if the content is unquestionably true.

I'm not saying that science is never taught in a similar way, mind. But when science is taught that way, I regard it as poor teaching.

 

[axocanth]

Hi again, James. Yes, I feel this already has the makings of a valuable exchange too. For now I just want to focus on one part of your recent posts, perhaps the most important. That is, while intuitions might vary about truth or approximate truth, there is a class of statements or theories that can be ruled out immediately, not even candidates for truth or truth-likeness (those containing non-referring terms). See below.

Before doing so, though, I'd refer you back to my post #146 on page 8. The post evoked a hostile response, taking me quite by surprise. Evidently I was misunderstood, perhaps as suggesting that the "Santa Claus theory" was somehow worthy of scientific attention or on a par with the greatest physical theories. That wasn't it at all. What I was trying to do -- as explicitly stated -- was to tweak intuitions on matters such as truth, understanding, explanation, and so on.

Now to business . . .

The history of science tends to suggest otherwise. While it is true that theories sometimes need to be thrown away completely, it is often the case that current theories are found to be correct in some appropriate approximation of a new and improved theory. We still guide our interplanetary spacecraft using Newton's law of gravity, because it works well enough, even though we have found that it's only an approximation of the "more correct" theory of General Relativity in an appropriate limit.

Newtonian gravity, to repeat an example, is highly confirmed. But we also know that it's false, in a technical sense. Or maybe it's mostly true. Or true in a lot of circumstances. Or true enough.

Here I think we need to be extremely careful about our wording. The class of statements/theories I alluded to the top are those containing "non-referring" terms. A non-referring term, as the name suggests, is one that refers to nothing, or stated more precisely, one that fails to refer.

Now, to even stand a chance of saying something true, the subject term must refer. e.g.

"Donald Trump [insert predicate here]"

Since "Donald Trump" is a referring term, the statement yields a true or false value depending on what predicate is inserted, i.e., what property or properties we attribute to the jolly orange giant. There's at least a chance of saying something true, or approximately so. E.g.

"Donald Trump has 100 legs" vs "Donald Trump is former US president"



By contrast, when we're dealing with non-referring terms, there is no possibility of saying something true, approximately true, or anywhere near the truth. E.g.

"The fountain of youth is in Florida" vs "The fountain of youth is not in Florida"

Both are untrue. Nothing true can be predicated of a non-referring term (with the exception "The fountain of youth does not exist").

This was my main reason for invoking Santa Claus in post 146, not to ridicule dear old Isaac or Albert lol. Surely all agree that any statement or theory about Santa Claus is just plain untrue. Quoting yourself from above, and any predictive power that it may have notwithstanding, the Santa Claus theory is not "mostly true", or "true in a lot of circumstances", or "true enough". It's just untrue. Do you agree?

Yes, sometimes we "suspend the rules" if you like, perhaps in a trivia quiz, and assert that "Santa's head reindeer is named Rudolph" is true. We would immediately retract, however, if someone asked "Do you mean to tell me there really is a dude called Santa Claus and that he really . . . ". I trust you get the picture.

Add to this, I assume we agree that the amount of genuine understanding that Santa theory yields is zilch. It does no genuine explanatory work at all, despite what those in the grip of the theory might think. Any sense of understanding is wholly specious.

In a nutshell, then, nothing true can be said of non-existent entities; nothing true can be predicated of a non-referring term (duly noting one exception). They explain nothing and they yield no genuine understanding whatsoever.



How does this apply to scientific theories? Well, in exactly the same way. Nothing true can be predicated of phlogiston, and presumably, inasmuch as it doesn't exist, most of us would agree that phlogiston (theory) explains precisely nothing. Typically, no one objects to any of this. Do you?

Things tend to get a bit more heated when we apply the same treatment to Newtonian theory. But if we take Einstein seriously, then the core posits of Newtonian theory (absolute space, absolute time, attractive gravitational force, etc.), like Santa Claus, do not exist. And vice versa, for that matter. On pain of inconsistency and contradiction, you can't have one foot in a Newtonian universe and the other in an Einsteinian universe.


In other words, then, you can't nail your colors to both masts at once. If we take both men literally (as opposed an instrumentalist stance), allegiance to one entails a complete disavowal to the other of any truth, approximate truth, "truth in a lot of circumstances", explanatory power, or genuine understanding yielded.

Similar considerations apply to the commonly heard claim that Einstein's theory "reduces" to Newton's (in cases of low gravity, low velocity, etc.), or as you put it, the latter "approximates" the former.

I've no objection at all to the claim that the predictions of Einstein's theory "reduce to" or "approximate" those of Newton's. And if you take a purely instrumentalist view of matter -- i.e. the two men's claims about reality are not to be taken literally -- you may sleep well. There's nothing more to worry you. Neither theory makes any truth claims, neither is trying to explain anything, neither is even attempting to describe what the universe is like, and neither brings any understanding of underlying causes and mechanisms.



By contrast, on a realist view with all the baggage that carries (explanation, understanding, etc.) it makes little sense to speak of one theory reducing to, or approximating, the other. Suppose we start near a black hole or something -- an "extreme" circumstance -- where the two theories yield wildly divergent predictions, then fly gradually back to Kansas where the respective predictions of the two theories are virtually indistinguishable, would anyone wish to claim that the 4-d spacetime manifold gradually disentangles itself into a Newtonian absolute space and absolute time that are independent of one another? Would anyone wish to claim that gravity, which was the curvature of spacetime in the vicinity of the black hole, proceeds to undergo some kind of identity crisis, gradually reverting to a good old fashioned Newtonian attractive force?

In an Einsteinian universe, there is no such thing as an attractive force, absolute space, and absolute time -- anywhere! -- and any assumption that Einstein's theory is true carries with it the implication that Newton's theory is not true, not "mostly true", not "true in a lot of circumstances", and not even "true enough" . . .

. . . unless of course you're willing to extend the same courtesy to Santa Claus theory.

Does, for example, the "Mummy and Daddy Do It" theory gradually reduce to the Santa Claus theory as we fly from India, where its predictions are wildly inaccurate, to Kansas where it "works" pretty well? Is it "mostly true", "true in a lot of circumstances", or "true enough"?

What do you say, James?


Thanks again for a thought provoking exchange. I may reply to other parts of your recent posts later, time permitting.

 

[axocanth]

@ James again. I'll respond to certain points you made earlier, for both of us (and perhaps others) to reflect on, as random thoughts occur to me. Hope it doesn't get too messy . . .

Perhaps. But on the other hand, consider an example where two people are flipping a coin and trying to guess the result of the next flip. It seems quite natural to say something like "Well, the coin has come up tails on the last four flips. So my theory is that on the next flip, the coin will turn up heads."

And that can only be a wild guess, if the coin is unbiased etc.

The gambler's fallacy! And our theorist might be described as a counter-inductivist. Whereas regular induction is a "more of the same" inference, the counter-inductivist reasons "it's time for a change".

Note, however, that this guy is able to explain his "rationale", as I suggested might be a prerequisite for applying the word theory, even if you see it as no better than a guess. He's deploying an invalid form of reasoning, you feel.

Note also that he would not describe what he's doing as a guess himself. You've already given us his "rationale", and if he knew the term he might say, "I'm using good counter-inductive reasoning". You think he's guessing; he thinks he's reasoning. Who has the final say on this? Or should you say, "He's reasoning, but reasoning badly. He's reasoning so badly that he'd be as well guessing."? If so, it's not really a guess, right?

Note further that just as you give short shrift to counter-inductive reasoning, there are those who hold regular inductive reasoning -- what you might describe as good scientific reasoning -- in equal contempt. They do not see it as a valid form of inference: no matter how many white swans have been observed, there is no good reason whatsoever to believe that the next observed swan will be white too. You'd be as well guessing!

Now, what kind of madman would say such a thing? A headless and repentant Russell's chicken might if he could still speak (the uninitiated are invited to google). Besides that, two big names come to mind immediately: One is Karl Popper, already covered in the thread. And I surely don't need to tell you the other. If other readers haven't sussed it yet, take a look at the quotes at the bottom of each of James' posts.


Meanwhile, it might be worth mentioning that there are also people who feel that the formulation (or "establishment") of a theory -- sometimes referred to as the "context of discovery" -- is not a logical, methodical, or rational process at all. Here's one of them . . .


"There is, of course, no logical way leading to the establishment of a theory but only groping constructive attempts controlled by careful consideration of factual knowledge."

- Albert Einstein



Finally, whatever we say about our gambler's reasoning, the probability of his theory being true is 0.5. Not bad at all!

Remember, what STOT advocates strongly imply -- downplaying the "assurance" of a layman's theory as much as possible while "up-playing" the assurance of a scientific theory as much as possible -- is that the latter is (far?) more likely to be true than the former.

How would you rate the chances of a theory randomly selected from all the theories in all the sciences (yes, even the social sciences *shudder* ) being true?

 

[TheVat]

In other words, then, you can't nail your colors to both masts at once. If we take both men literally (as opposed an instrumentalist stance), allegiance to one entails a complete disavowal to the other of any truth, approximate truth, "truth in a lot of circumstances", explanatory power, or genuine understanding yielded.

What's interesting about Newtonian gravity theory is that it can be both false and retain explanatory power in the sense that we can apply his law, enshrined in that famous formula, and make useful predictions. Here is an analogy for you on this curious state of "it is crap, but still works."

Bob and Alice are in Taipei and Miami, respectively, roughly the same latitude. Both set out for the North Pole along their respective lines of longitude. Now in their world there is an old theory that an invisible attractive force acts between them, drawing them closer and closer until they meet up at the pole. This theory, when used, makes accurate predictions of polar encounters between northbound objects which move at the same speed and start at the same latitude.

Eventually a new theory comes along, based on the concept of movement on the surface of a sphere. Alice and Bob are following curved paths and it is simple geometry (and perhaps hormones) that is bringing them together. Lines of longitude all intersect at poles. The "force" is a pseudoforce, not real.

So, while people reject Clausian theory after, say, age 9, based on various empirical observations that directly contradict it, they might continue to use the math in the Attractive Geography theory I just mentioned, even as they are aware that the attraction is a pseudoforce. Indeed teachers might use the AG theory with children in elementary school, perhaps saying, "it's not quite right to say Alice and Bob are pulling on each other, but that's for next year's unit on Moving Around on a Rotating Sphere." (at this point, my analogy has collapsed into silliness, but I think it has served its purpose)

Later, in college, advanced students can delve into Bob and Alice going north on jets and the Coriolis effect.

 

[axocanth]

Well, there are alternative measures of "goodness". For instance, we could ask whether an explanation is useful, even if it's not "true". But this is a whole other can of worms.

For scientific purposes, a theory -- whether true or false -- that yields accurate predictions can certainly be "useful". We can send TheVat to the moon using a false theory.

But for the life of me, though, I can't imagine in a scientific context what could be "useful" about a false explanation. Can you think of an example?

 

[axocanth]

TheVat, you posted at almost the same time I did, before I had read it.

In your example, is it not the predictions of the respective theories that are being put to practical use (if any)?

The false explanation -- "there is an attractive force at work" -- surely does nothing but implant a spurious sense of understanding. On the other hand, an explanation of "It's as if there is an attractive force at work (but there is not)" is not false.

What do you think?

 

[TheVat]

The false explanation -- "there is an attractive force at work" -- surely does nothing but implant a spurious sense of understanding. On the other hand, an explanation of "It's as if there is an attractive force at work (but there is not)" is not false.

I think the use of "as if" is what I was driving at. As If allows us to use our intuitions (Alice and Bob are being pulled together, in my example) and get some purchase on what is happening and make calculations. In high school, my science teacher told us about gravitational "force," showed us the equation, and left it for college to teach "actually all objects simply follow their spacetime geodesic but the electrostatic forces in the Earth's crust and the floor and your chair seat are opposing the unimpeded motion of your butts along that geodesic."

Advanced learning is often where our ordinary intuitions are violated, and the incompleteness of "as if" is better understood. (The world of my Alice/Bob example is a dumbed-down one, for sure, and we don't really have to start teaching about trips to the North Pole with Alice and Bob attracted to each other. In our world, even elementary school kids can see the Earth as a globe.)

I can see instrumentalism thrives where an engineering mindset is useful. Building a bridge, I will consider gravity a force, and use Newtonian physics. Building a starship that travels up to .15 C and planning a voyage to Proxima Centauri, I will use GR and toss the false intuitions and assumptions of Newton. We can hope that scientists have reached the point where it's easier to admit, "what we have now is the best explanation so far, and it is working at a practical level, but we are always prepared for some of our intuitions as to how it works to be modified or replaced." If there's a way to teach young students that, I'm all for it.

 

[axocanth]

@ TheVat above

That all sounds quite sensible to me. I'd just draw attention to all this talk of explanations and best explanations, often coming from scientists or lay science defenders who, at the same time, may be reluctant to assert that their theories are true. This reluctance may be due to various reasons, e.g. intellectual modesty (most welcome! - but in this case misplaced) or perhaps a desire to distinguish themselves from their religious adversaries. We might hear, for example:


"That's what separates science from religion. You guys claim to know The Truth; we don't. I claim only that evolution is the best explanation. Everything in science is tentative, nothing is final, you're not gonna get Absolute Truth from science. Today's theories are liable to be supplanted by something better in the future."


Now, unless the scientist takes himself to be in the same business as the Brothers Grimm, any such talk is confused and misguided. Truth is once again being smuggled in through the back door.

The only reason a scientist would be interested in "the best explanation" -- unless he's eager to provide entertainment -- is if there is some link between "best explanation" and "truth".

Now, many thinkers do feel there there is a link between the best explanation and truth. This is the celebrated Inference to the Best Explanation (IBE), as you already know, viz., we are licensed to infer from "X is the best explanation" to "X is true", or some variation thereof. IBE is invariably advanced by those defending some version of scientific realism.

I make no distinction between truth and Truth, and truth and absolute truth, and until someone provides a coherent account of these putative distinctions (no one ever has, and no logician I've heard of recognizes any such distinctions) I'll continue to do so.

Thus, for a scientist to assert evolution (say) is the best explanation can be understood as asserting either:

(i) Evolution is a ripping good yarn, something like Charlie and the Chocolate Factory. It is superior to the Creationist explanation of the same phenomena insofar as it puts your kids to sleep faster at bedtime, or

(ii) Evolution is true (= True = absolutely true = the final Truth)


And if there is indeed a link between best explanation and truth, and evolution is subsequently and justifiably overthrown, then it is not the best explanation. You could argue -- pointlessly! now or in in retrospect -- that it is/was the best explanation available to us at this/that time. But no one I know of believes there is a link between truth and the second best, third best, or sixteenth best explanation.

 

[axocanth]

That might depend on how you want to define falsification. On its face, the word "falsify" means "to prove something false", so there's that. But in science we often (always?) can't prove theories to be true. Which was Popper's point, I suppose...

Just to clarify once again, Popper does not merely claim that scientific theories cannot be proven. You're not gonna see your name in lights by saying that scientific theories cannot be proven. Just about every Tom, Dick, and Harry thinks so too nowadays.

Swearing allegiance to David Hume, Popper goes much further: There is never any good reason whatsoever to believe that a scientific theory is true.

"Good reason" here excludes things like gut feelings and the gypsy told me.

Any Popperians left out there? Please make yourselves known to our cabin crew.

 

[axocanth]

I can see instrumentalism thrives where an engineering mindset is useful. Building a bridge, I will consider gravity a force, and use Newtonian physics. Building a starship that travels up to .15 C and planning a voyage to Proxima Centauri, I will use GR and toss the false intuitions and assumptions of Newton. We can hope that scientists have reached the point where it's easier to admit, "what we have now is the best explanation so far, and it is working at a practical level, but we are always prepared for some of our intuitions as to how it works to be modified or replaced." If there's a way to teach young students that, I'm all for it.

OMG!! How did this slip past me!

Referring back to my second last post, you had better hope that it's not the best explanation "so far" -- such a beast is of no interest to science, assuming they're not treating their work as showbiz. Even assuming that IBE (inference to the best explanation) is a valid form of inference at all, you'd better hope that your explanation is the best of all possible explanations, the best explanation period, full stop.

It's an all-or-nothing kind of thing. The second best explanation doesn't even win a stuffed elephant and a bus ride back to Kansas. There is no reason at all to think that it is true. If #1 is true, assuming mutual incompatibility, then all the others are false.

By the way, what's the second best explanation at present after evolution? The other C-word? Er, does it win any prizes?

 

[DaveC426913]

Swearing allegiance to David Hume, Popper goes much further: There is never any good reason whatsoever to believe that a scientific theory is true.

Pretty sure we can close the book on The Germ Theory of Disease and the Atomic Theory of Matter.

 

[axocanth]

Pretty sure we can close the book on The Germ Theory of Disease and the Atomic Theory of Matter.

Maybe! Who knows! Don't look at me!

What we can say with certainty, though, is that scientists -- including the very finest -- have expressed similar sentiments in the past and been quite wrong. The luminiferous aether, for example, despite what you might have read in "Whiggish" histories of science, was not -- at least by many scientists -- regarded as a mere hypothetical posit or a "place holder" with no evidence to support it. There's a regrettable tendency to rewrite history on such matters. No, its existence was proven beyond any reasonable doubt, as certain as the very air we breathe, you'd have to be quite mad not to believe in the aether - not at all unlike how Richard Dawkins speaks of evolution today. The evidence is overwhelming.

Surely you exaggerate, Mr axocanth? Judge for yourself; a lesson in intellectual humility is always salutary . . .


"Whatever difficulties we may have in forming a consistent idea of the constitution of the aether, there can be no doubt that the interplanetary and interstellar spaces are not empty, but are occupied by a material substance or body, which is certainly the largest, and probably the most uniform body of which we have any knowledge."

- J. C. Maxwell


"We know the luminiferous ether better than we know any other kind of matter in some particulars. We know it for its elasticity; we know it in respect to the constancy of the velocity of the propagation of light for different periods"

- Lord Kelvin



And as J. J. Thomson said as late as 1909, supposedly after Einstein had disproved (cf. falsified) its very existence . . .

"The ether is not a fantastic creation of the speculative philosopher; it is as essential to us as the air we breathe. . . . The study of this all-pervading substance is perhaps the most fascinating and important duty of the physicists"