A Simple Question: Should We Believe Scientists?

[NoShips]

This, however, is to attack a strawman.

I was attacking direct quotes (perhaps you didn't listen to the videos posted). If that's a strawman, then Neil deGrasse Tyson is his name.

My recollection is that most scientists do not claim that science searches for "truth", but for practical models of reality. As models they are necessarily incomplete.

This is a good point. It's undeniable that many scientists these days, especially in the more abstruse disciplines (quantum physics, say), are wont to talk of "models", wary of any talk of "truth", and as you say, models, unlike statements and hypotheses, don't seem to be the kind of beasts to which the predicates true and false apply. Whether or not this represents the position of "most" scientists, I really couldn't say. It's equally undeniable that many scientists do speak of their work as a search for truth.

It's also comforting to know that not only I find Dawkins and deGrasse Tyson insufferable. Cheers! :-)

[SciameriKen]

Well good thing you are not a quark right?

What you are not grasping is in this world being mostly right is enough to get the job done.

Mostly right? This argy-bargy began with Prof deGrasse Tyson importuning us, "It's not something to say I choose not to believe e=mc2; you don't have that option."

I say we do have that option. Are you on my side now, Ken, or do you insist that e=mc2 is forever invulnerable to revision? Noli me tangere! If so, I'd like to hear your justification. A gut feeling or what?

Can't happen? Remember what J.C. Maxwell told us about the luminiferous aether being the most highly confirmed entity in all science? Prof Maxwell might also have told me I have no option but to believe.


P.S. What you (and Forest and BiV) are failing to grasp is that false theories yield true predictions too.

Does the theory "all birds can fly" (in conjunction with the usual auxiliaries) yield any true predictions ? Ans: yes -- lots of 'em! Is the theory true? Ans: no

Does the theory "all birds are flightless" (in conjunction with the usual auxiliaries) yield any true predictions ? Ans: yes -- lots of 'em! Is the theory true? Ans: no

Does phlogiston theory (in conjunction with the usual auxiliaries) yield any true predictions ? Ans: yes -- lots of 'em! Is the theory true? Ans: no

Does Newtonian mechanics (in conjunction with the usual auxiliaries) yield any true predictions ? Ans: yes -- lots of 'em! Enough to get us to the Moon and back. Is the theory true? Ans: no

Does Einsteinian relativity entail (in the logical sense) certain observational consequences? (nukes and such, as BiV pointed out). Ans: yes. Have these consequences been confirmed? Ans: not half! Do these observational consequences entail the truth of Einsteinian relativity? Ans: no.

(Einstein himself was fully aware of this, of course)

Underlying all of this is evidence based reasoning. Your theory of birds will obviously have to be updated won't it?

Ultimately what you are failing to grasp is that you don't go backwards. You don't ignore evidence to make phlogiston work again. At this present moment in time Neil is absolutely correct - you can't deny e=mc^2- you can't simply wish it away by ignoring evidence.

[NoShips]

I'm afraid you neglected to answer the question. Here it is again:

"I say we do have that option. Are you on my side now, Ken, or do you insist that e=mc2 is forever invulnerable to revision? Noli me tangere! If so, I'd like to hear your justification. A gut feeling or what?"

[SciameriKen]

I'm afraid you neglected to answer the question. Here it is again:

"I say we do have that option. Are you on my side now, Ken, or do you insist that e=mc2 is forever invulnerable to revision? Noli me tangere! If so, I'd like to hear your justification. A gut feeling or what?"

My answer is there in the above, but to make it explicit - no. Current evidence supports it but if new evidence overturns it then we move on. It's called progress.

But you always move forward. The war on science is to ignore evidence - to go backwards.

Now explicitly answer my question. Do you believe scientists?

[NoShips]

Now explicitly answer my question. Do you believe scientists?

Sometimes

[Forest_Dump]

I suppose now we are getting closer to a rational for citing Hume who, having lived in the 17th century, got a number of things "wrong" and therefore can't be cited as though he were "true". By the way, Feynman also admits that he got some things wrong so I guess HIS statement that NoShips cited also cannot be considered necessarily "true".

[TheVat]

This is where your Ignorance Slip is showing, Noships. "Strictly speaking" F=ma is still true, but in a limited case. That is NOT the same as "false." It's these casually dropped inaccurate remarks on your part that undermine your thesis.

Strictly speaking the theory "all mammals lay eggs" is still true, but in a limited case. Stick to a monotreme farm and you'll be just fine.

What you're telling me is that f=ma is true in all situations... except those where it's not true. Right?

As for E=mc2 turning out false....hey, that would be great, we could stop worrying about nuclear warheads and learn to love the Bomb! But, alas, the relationship between matter and energy shows no signs of altering, so you may be in for a disappointment. Well, actually, you should be happy because it means the sun keeps shining and warming the Earth so we don't turn into a ball of ice.

False analogy, pal. If you're gonna argue that bombs exploding prove E=mc2, I might as well argue that combustion proves the existence of phlogiston.

No doubt bombs will continue to explode, and stuff will continue to combust: how we describe these phenomena may not be so irrefragable.

You misconstrue my analogy. The energy output from the sun, or an H-bomb, or a reactor, is measurable. The output of phlogiston isn't, and never was. That's why it was discarded as a theory of combustion. E=mc2 is relation between matter and energy that has been measured and confirmed over and over again. Our theory (or model, if you prefer that term) of WHY energy and matter are convertible in this way could change, but that equation won't. Just as Galileo's measurement of the acceleration due to gravity on Earth still holds (even though his model has been superseded in some respects), so will E=mc2. The refinement of underlying models is not the same as a rejection of the usefulness of what came before. As Ken pointed out, F=ma is still a perfectly sound equation for 99.999 percent of the physics that is done with moving bodies on and around Earth. Don't confuse "wrong" and "incomplete," or think that the latter adjective is somehow a condemnation or rejection. In physics, it may just indicate an old layer of established fact that is still legitimate in the context of non-relativistic speeds and terrestrial scales of magnitude.

Real science rarely involves tearing down the Temple. It's usually more like adding a new wing and a jacuzzi and updating some of the wiring.

[NoShips]

You misconstrue my analogy. The energy output from the sun, or an H-bomb, or a reactor, is measurable. The output of phlogiston isn't, and never was. That's why it was discarded as a theory of combustion. E=mc2 is relation between matter and energy that has been measured and confirmed over and over again. Our theory (or model, if you prefer that term) of WHY energy and matter are convertible in this way could change, but that equation won't. Just as Galileo's measurement of the acceleration due to gravity on Earth still holds (even though his model has been superseded in some respects), so will E=mc2. The refinement of underlying models is not the same as a rejection of the usefulness of what came before. As Ken pointed out, F=ma is still a perfectly sound equation for 99.999 percent of the physics that is done with moving bodies on and around Earth. Don't confuse "wrong" and "incomplete," or think that the latter adjective is somehow a condemnation or rejection. In physics, it may just indicate an old layer of established fact that is still legitimate in the context of non-relativistic speeds and terrestrial scales of magnitude.

Real science rarely involves tearing down the Temple. It's usually more like adding a new wing and a jacuzzi and updating some of the wiring.

Ah, it seems while everyone is willing to pay lip service to the fallibility of science, that fallibility always seems to lie with some other sucker's theory; mine is solid as the Rock of Gibraltar, thank you very much.

Who knows, E=mc2 might survive unscathed until the universe suffers the heat death, and folks in the 32nd century will be praising the uncommon prescience of their barbaric forebears. Your take on these matters is a lot more sanguine than my own, BiV; perhaps just a reflection of my own curmudgeonly nature.

Three things to say though:

1. My layman's understanding is that relativity is already known to be inadequate; as far as I understand, Einsteinian relativity is quite incompatible with quantum physics, yielding wildly inaccurate results at the level of subatomic phenomena. Perhaps the physicists among us can help with clarification. Does e=mc2 hold at the quantum level? If not, it's false.

(No use arguing it's "right sometimes" -- reminds me of when I asked one of my EFL students "Is your car reliable?" and he replied "sometimes". To be reliable sometimes is to be unreliable, and for an equation to be right sometimes is for that equation to be false.)

2. It's conceivable e=mc2 will survive, but may suffer the same fate as f=ma, i.e., the equation is retained, but is no longer regarded as true tout court. Everything you've said about e=mc2 above ("measured and confirmed over and over again", etc), BiV, might equally well have applied to f=ma... and look what happened to that. Seems to me your confidence in the immortality of e=mc2 is something of an article of faith.

3. It's also possible that our conceptual/theoretical apparatus will undergo a radical upheaval, and rather than us coming to regard e=mc2 as false (but still truth evaluable nevertheless), it will simply become irrelevant, not even a candidate for truth or falsity -- a bit like the old nugget in the philosophy of language "the present king of France is bald". Hey wait! There is no present king of France. And there is no aether, caloric fluid, or phlogiston.

Are these scenarios likely? I really couldn't say, and, I daresay, neither could you (show us your calculations otherwise). None, though, are particularly rare in the history of science. All have precedents.

[NoShips]

From Wiki...

Goldbach's conjecture is one of the oldest and best-known unsolved problems in number theory and all of mathematics. It states:

Every even integer greater than 2 can be expressed as the sum of two primes.


Stop press: mathematicians discover an even integer, a googol digits long, that cannot be expressed as the sum of two primes.

Trivia time, folks: You're on a TV quiz show with a fat prize of $50,000 awaiting the correct answer. All you have to do is answer the following multiple choice question correctly: Is Goldbach's conjecture

(i) true
(ii) false
(iii) incomplete
(iv) almost true, really sound and valid and jolly useful, so get off my case, loser

[SciameriKen]

IV

[NoShips]

LOL

Thanks for playing. Dignity just cost you 50,000 bucks

[NoShips]

BraininVat, I'd like to draw your attention to two comments you made in another thread which appear incongruous with your most recent stance. Here's a link to the thread in question:

viewtopic.php?f=10&t=31851

Firstly, you say this (page 1, post 20):

"These chats (and we've had many of them in the philosophy fora) seem to be driven by semantics. Truth is an umbrella word that covers several kinds of statements about reality and our observations. They all get referred to as truth, which is what leads to the confusion. There's definitional truth, like F=ma or "cats are furry bipeds that purr and sleep 20 hours a day.""

Now, if f=ma is a definitional truth, as you claim in the quote above, it cannot be true most of the time, or almost true, or as you put it yourself earlier on this page "As Ken pointed out, F=ma is still a perfectly sound equation for 99.999 percent of the physics that is done with moving bodies on and around Earth."

A definitional truth is true simpliciter. Is it not so? There are no exceptions to a definitional truth.



Secondly you say this (page 2, post 5):

"But all statements seem to me to lie within a "web of belief" (as Quine called it) where truth relies on a complex network of commonly held propositions about the world."

It seems to me this commitment to a Quinean web of belief contradicts your insistence on the immutability of the proposition e=mc2. As a reminder, you told us above: "Our theory [...] of WHY energy and matter are convertible in this way could change, but that equation [e=mc2] won't".

In such a holistic Quinean web of belief, the kind you purport to subscribe to, all statements are susceptible to revision. Right? And that includes e=mc2. Only time will tell whether it does get revised; given your Quinean presuppositions, however, the possibility that it will get revised cannot be ruled out of court a priori as you're doing here.



Pssst! It would be handy if you'd number the posts in each thread.

[NoShips]

Hey, look what I found :-)

viewtopic.php?f=2&t=6938 (post 5)

"In any event, one must understand an equation before using it. The famous equation E = mc2 is only valid under certain circumstances. The more correct version E = ymc2 isn't always true, since it doesn't include potential energy, nor kinetic rotational and vibrational energies.

And so on..."


And once again, despite the moral support from the above poster (Lincoln), I can only cringe at the language-mangling. To say an equation "isn't always true" is incoherent gibberish; one ought to say the equation is false -- even if it does yield correct predictions in some cases.

Look at at it this way, remember our scenario about 99 black and 1 white cat? The hypothesis "all cats are black" is false! It is not "true some of the time"; it is not "true on weekdays and false at weekends"; it is false, false, FAAAALLLSSSEEEEE!!!! It is false, period; it is false today, yesterday, and tomorrow. It is false every day, and twice on Sundays.

The hypothesis may yield many true predictions (e.g. "the next cat I see will be black"), but as we examined, not only true hypotheses/equations yield true predictions; false ones are nice that way too. Got us to the Moon and all that, eh?


Edit: If that wasn't clear enough, trivia time again, folks: Is the hypothesis "all British prime ministers are men"

(i) True
(ii) False
(iii) Not always true: true when a dude is in power and false when Maggie Thatcher and Theresa May get in?

[SciameriKen]

Hey, look what I found :-)

http://www.sciencechatforum.com/viewtop ... f=2&t=6938 (post 5)

"In any event, one must understand an equation before using it. The famous equation E = mc2 is only valid under certain circumstances. The more correct version E = ymc2 isn't always true, since it doesn't include potential energy, nor kinetic rotational and vibrational energies.

And so on..."


And once again, despite the moral support from the above poster (Lincoln), I can only cringe at the language-mangling. To say an equation "isn't always true" is incoherent gibberish; one ought to say the equation is false -- even if it does yield correct predictions in some cases.

Look at at it this way, remember our scenario about 99 black and 1 white cat? The hypothesis "all cats are black" is false! It is not "true some of the time"; it is not "true on weekdays and false at weekends"; it is false, false, FAAAALLLSSSEEEEE!!!! It is false, period; it is false today, yesterday, and tomorrow. It is false every day, and twice on Sundays.

The hypothesis may yield many true predictions (e.g. "the next cat I see will be black"), but as we examined, not only true hypotheses/equations yield true predictions; false ones are nice that way too. Got us to the Moon and all that, eh?


Edit: If that wasn't clear enough, trivia time again, folks: Is the hypothesis "all British prime ministers are men"

(i) True
(ii) False
(iii) Not always true: true when a dude is in power and false when Maggie Thatcher and Theresa May get in?

All I gotta say to that is sorry that you live in the real world and you are not a quark. What is your larger point?

[TheVat]

Noships, you are being misled by the way physicists use terms, in a field specific way. The fact that E=mc2 doesn't work at certain levels doesn't mean it is "false." It has a domain, and in that domain it is quite reliable. Regarding....

It seems to me this commitment to a Quinean web of belief contradicts your insistence on the immutability of the proposition e=mc2. As a reminder, you told us above: "Our theory [...] of WHY energy and matter are convertible in this way could change, but that equation [e=mc2] won't".

It doesn't, but I'm not a good enough physics teacher to explain. Lincoln would be, but he is absent, alas. You also say that relativity must be "wrong" because there are quantum-level events where it doesn't work properly. Again, it's not wrong, but rather is not the best model for doing the math on quantum events. You've picked an area of science where things are complex, and require study.

What you are doing, essentially, is arguing something that sounds like "Quantum entanglement doesn't explain how the carburetor on my old car works. So it must be wrong." Perhaps mitchellmckain could provide some insight here.

PS - Einstein recognized the limited domain of certain physics theories. That's why Special Relativity was called "Special" - in physics, that word refers to a limited case. When he developed a theory that encompassed gravity and all the mass in the universe, he then called that General Relativity. And, on those large scales, it works great.

[NoShips]

Noships, you are being misled by the way physicists use terms, in a field specific way. The fact that E=mc2 doesn't work at certain levels doesn't mean it is "false." It has a domain, and in that domain it is quite reliable.

Sorry, it does mean that the equation is false. Taking for granted your comments above, then:

"E=mc2 [within a certain domain]" is a true statement
""E=mc2" is a false statement

in exactly the same way that

"All mammals lay eggs [as long as I stick to monotremes]" is a true statement
"All mammals lay eggs" is a false statement

It doesn't [constitute a contradiction], but I'm not a good enough physics teacher to explain.

Still looks awfully like a contradiction to me, friend. Other members can decide for themselves. Here's what Quine himself has to say on the matter:

(as a reminder to our readers: BiV claims both to subscribe to Quinean holism and that the statement "e=mc2" is immune to revision)


"If this view is right, it is misleading to speak of the empirical content of an individual statement -- especially if it be a statement at all remote from the experiential periphery of the field. Furthermore it becomes folly to seek a boundary between synthetic statements, which hold contingently on experience, and analytic statements which hold come what may. Any statement can be held true come what may, if we make drastic enough adjustments elsewhere in the system. Even a statement very close to the periphery can be held true in the face of recalcitrant experience by pleading hallucination or by amending certain statements of the kind called logical laws. Conversely, by the same token, no statement is immune to revision. Revision even of the logical law of the excluded middle has been proposed as a means of simplifying quantum mechanics; and what difference is there in principle between such a shift and the shift whereby Kepler superseded Ptolemy, or Einstein Newton, or Darwin Aristotle?"

-- "Two Dogmas of Empiricism"

(You'll notice he does not say "No statement is immune to revision ... except e=mc2")

Einstein recognized the limited domain of certain physics theories. That's why Special Relativity was called "Special" - in physics, that word refers to a limited case. When he developed a theory that encompassed gravity and all the mass in the universe, he then called that General Relativity. And, on those large scales, it works great.

On the question of "domains", see above. As for "working great", this is entirely besides the point. Right now we're examining claims about truth (your own and those of deGrasse Tyson); not claims about whether such-and-such a theory/equation works.

The widely recognized fact that false theories can work extremely well is not contested, not by this quark anyway. Got us to the Moon and all that, eh. But a theory's working is an issue quite orthogonal to that of its truth.

[TheVat]

You are aware that it was that ol' Newtonian fizz that got us to the Moon, right? For something that you want to define as falsified, I would say that's some pretty ass-kicking "false" theory. And I'm sure you are also aware (because who would engage in a discussion that turns on physics examples without knowing some physics) that Einstein's GR field equations are why our satellite GPS systems work at all. Or why we can predict Mercury's precession to many decimal places. (There's a whole thread here somewhere on that) I don't think Quine was talking about measurable equivalences like, say, E=mc2, when he was talking about things that may be subject to revision. No "drastic adjustments" need to be made elsewhere in the system for that matter/energy equivalence to continue to be acceptably accurate. The same goes for Earth pulling on you with an acceleration of 9.8 m/s2. We understand the context of Galileo's measurement and, even if the Moon crashed into us and our G increased due to the increase in total mass, it would not invalidate that Earth, for several billion years had a certain mass (6 x 10E24 kg, IIRC)....and that that mass will accelerate a falling Noships at 9.8 m/s2 (until he reaches terminal velocity due to air resistance....or lands, ouch!) (sorry, let's just stick with bowling balls or U.S. Senators...)

In physics, having the consistent measurements and making accurate predictions, is having mathematical tools that aren't quite so "orthogonal" to theoretical truth. Physics is not taxonomy, a field from which you draw your example of dubious mammal definitions. The definition of mammal can change tomorrow, and my Quinean side would quite understand. Perhaps monotremes will be kicked out of the club. Some kind of analytic prestidigitation will do the job. Not too interesting. But, unless Quine is actually an uber-skeptical stance fellow, he would have to admit the sun will shine and will continue to fuse hydrogen to do so. I'm not entirely sure you realize how very very demonstrable that matter-energy relationship is. Indeed, it doesn't much care what we say or do or how we revise this and that. The sun shines, the Earth spins, gravity sucks. Tyson isn't trying to establish absolute truth, he's just trying to indicate that some things we know are foundational and that we can move on and get all Quinean about other stuff that is more ambiguous and fleeting.

[NoShips]

Hmm, we don't seem to be getting anywhere. You still good for beer and poker tonight, dude?

Just remember, the statement "I have four diamonds which is pretty much the same thing as a flush" is false.

And bring your own beer *poke*

:-)

[Eclogite]

The only absolute is, there are no absolutes.

That aught to end the discussion, but I fear it may continue intermittently for years.

[NoShips]

You are aware that it was that ol' Newtonian fizz that got us to the Moon, right? For something that you want to define as falsified, I would say that's some pretty ass-kicking "false" theory. And I'm sure you are also aware (because who would engage in a discussion that turns on physics examples without knowing some physics) that Einstein's GR field equations are why our satellite GPS systems work at all. Or why we can predict Mercury's precession to many decimal places.

Yes, I'm quite aware that Newtonian mechanics got us to the Moon, and of the relationship between GR and GPS systems. Practical applications, or that true predictions can be derived from both theories, has never been the issue here -- I neither deny nor contest this. The issue at hand is their truth, and the degree of reluctance among our members to admit falsity where the most basic logic demands is somewhat dismaying, if not entirely surprising, choosing rather to whitewash the issue with irrelevancies (practical applications) and implications of incompetence.

Presumably Steven Weinberg's scientific competence is not in doubt. His candour is, at least, refreshing:

"There are plenty of imaginable theories that are logically perfectly consistent but nonetheless wrong. For instance, there is nothing logically wrong with Newtonian mechanics."

-- Steven Weinberg (from "Facing Up", essay 6, "Nature Itself", his emphasis)

[NoShips]

I'm growing to like this Steven Weinberg dude a lot!

With a view to Braininvat's pertinacious, and I might even be inclined to add perverse, insistence on the immutability of E=mc2, I offer the following observations from Weinberg's essay, "The Heritage of Galileo"

"The struggle for religious and intellectual liberty is evidently not over. And in this struggle, the influence of science is surely one of our greatest aids. This is not because of the certainty of scientific knowledge, but precisely because of its uncertainty. Seeing scientists change their minds again and again about matters that are accessible to experiment and mathematical analysis, we are warned against giving the power of criminal jurisdiction to any religious authority that claims to speak with certainty about matters that are beyond human experience."


While the iron is still hot, it might be salutary for us to scrutinize once more Richard Feynman's remarks from earlier in the thread (pp 4-5), which I believe complement the Weinberg quote very nicely:

"Science alone of all the subjects contains within itself the lesson of the danger of belief in the infallibility of the greatest teachers in the preceding generation . . .As a matter of fact, I can also define science another way: Science is the belief in the ignorance of experts."

It came as a painful shock indeed, after many centuries of unshakable faith in the infallibility of Aristotle, when the Master turned out to be mistaken on innumerable matters of fact and theory. Newton, likewise, after enjoying two centuries of hegemony wherein his mechanics were widely perceived as having delivered the holy grail of science -- certain knowledge -- ended up adumbrating Feynman's cautionary admonition.

Your "lesson" is, or at least ought to be, clear by now, professor.

Yet some among us still aspire to have the equations of our greatest teachers carved in stone.

[SciameriKen]

The only absolute is, there are no absolutes.

That aught to end the discussion, but I fear it may continue intermittently for years.

Absolutely!

[NoShips]

Make up your own mind whether this is on or off topic, but since we're doing quotes, here's one for Eclogite taken from J. Bernard Cohen's "Revolution in Science" which I'm currently engrossed in during breaks from Weinberging.

First a wee reminder: In another thread (entitled "Emergence") yours truly had been plaintively bewailing, inter alia, the predictive impotence of evolutionary theory. Eclogite took umbrage, issuing the following challenge:

"Give me an environment. Specify a family, genus or species. Give me a change in the environment. I'll give you a prediction."

to which I suggested

"Ok, it gets hotter in Colombia. What might we expect from bird-eating spiders?"

As best I can tell, no answer was forthcoming. Perhaps the following passage (from Cohen) will help explain why:

"The revolutionary quality of Darwin's thinking is made manifest in the attacks upon Darwin for not having followed the simple prescribed model that was supposed to be the accepted way of doing science. In order to see the extent to which Darwinian evolution by natural selection represented a departure from traditional norms of scientific thought, for instance as found in the Newtonian natural philosophy, one has only to take account of the fact that Darwinian evolution is nonpredictive, but nevertheless causal. That is, although by natural selection and various other subdoctrines Darwinian evolution assigns a cause to the process whereby present species result from natural selection, this science is unable to predict what the future course of evolution will be, even given the conditions of the environment, with some degree of precision. In other words, Darwin showed that a science can give a "satisfactory explanation of the past," even when "prediction of the future is impossible."

[Lomax]

Then it's hard to tell what you can possibly think Feynman meant. Did he mean that science is believing that the experts are so dumb they are never worth listening to? One, so to speak, doubts it. Otherwise you will have to explain to me the point of the Feynman quote and why you think it works in your favour.

Hey dude, hope my comments didn't come across as curt. Wasn't meant that way.

Not at all, and sorry if my own curtness (which was intended ad argumentum, not ad hominem) gave you that impression. Still -

What I'm trying (clumsily) to say is that by all accounts Richard Feynman was a very smart chap. Therefore I find it hard to believe he's saying nothing more than a jejune "scientists don't know everything". My granny could have told you that!

I suggested my own interpretation earlier (and, of course, I'm far from certain that it's right). Seems to me Prof Feynman is warning us to be wary of believing scientific experts; not because they're 'dumb' (sigh!), or not because they're inadequately qualified, but rather because scientific claims are, by their very nature, susceptible to revision.

Let's try an example. And let's make the stakes high to prevent flippant answers. An evil demon has taken one of us hostage, oh let's say BraininVat, and is holding a gun to his head. We're told:

"Scientific experts currently estimate the age of the Earth to be 4.5 billion years. You can choose to bet for or against this being the correct answer. I'm in a good mood so let's say I'll allow a margin of error of half a billion years on either side. Oh, by the way, I'm omniscient. If you bet wisely, this wretch goes free; otherwise he eats lead. Place your bets, please."

I'd bet against, and no, not because the experts are dumb. These things do tend to get revised a lot though. How about you, Lomax?

A life hangs in the balance...

- I don't see how this has any particular consequence beyond a recognition that all experts should be treated as if they were mammals. It doesn't change the fact that some mammals are better informed than others. By all means we are constantly revising science; but let's be fair, and aware of the comparatively unreliable and unuseful legacies of non-science, anti-science, and pseudoscience.

[NoShips]

- I don't see how this has any particular consequence beyond a recognition that all experts should be treated as if they were mammals. It doesn't change the fact that some mammals are better informed than others. By all means we are constantly revising science; but let's be fair, and aware of the comparatively unreliable and unuseful legacies of non-science, anti-science, and pseudoscience.

I see nothing objectionable there, Lomax. Dang! :-)

The fight back then was against overly dogmatic positions in science. Where ya been? We've moved on to new fights.

[Eclogite]

First a wee reminder: In another thread (entitled "Emergence") yours truly had been plaintively bewailing, inter alia, the predictive impotence of evolutionary theory. Eclogite took umbrage, issuing the following challenge:

"Give me an environment. Specify a family, genus or species. Give me a change in the environment. I'll give you a prediction."

to which I suggested

"Ok, it gets hotter in Colombia. What might we expect from bird-eating spiders?"

As best I can tell, no answer was forthcoming. Perhaps the following passage (from Cohen) will help explain why:

No. The "Why" is that the discussion on that thread moved well past the point where my observations would have been relevant. I believe I mentioned this at one point, but that may just be a recollection of an intention.

As far as I can now recall I could find no correlation between ambient temperature and arachnid habit in this context. However, the increase in temperature would likely change the mix of bird species, through direct and indirect means. This would probably affect the success of these spiders, either increasing or decreasing their numbers and doubtless altering some behaviours, dependent upon the particular birds that became the favoured target.

[NoShips]

As far as I can now recall I could find no correlation between ambient temperature and arachnid habit in this context. However, the increase in temperature would likely change the mix of bird species, through direct and indirect means. This would probably affect the success of these spiders, either increasing or decreasing their numbers and doubtless altering some behaviours, dependent upon the particular birds that became the favoured target.

Forgive me, Eclogite, if I say this all sounds hopelessly vague -- and given the putative randomness of mutation postulated by Darwinian-based theory, any prediction would, by necessity, have to be hopelessly vague, as Cohen correctly points out.

Which, if any, of the following would be inconsistent with evolutionary theory?:

(i) something happening (not being provocative -- in all sincerity this is how your "prediction" rings to me)
(ii) nothing at all happening -- business as usual for our hairy pals
(iii) bird-eating spiders become extinct -- in this particular ecology anyway


Edit: See, what worries me is that no matter what happens, the more devoted Darwinians will, ex post facto, of course, declare another triumph for their theory -- "yes, we saw this coming"

[NoShips]

- I don't see how this has any particular consequence beyond a recognition that all experts should be treated as if they were mammals. It doesn't change the fact that some mammals are better informed than others. By all means we are constantly revising science; but let's be fair, and aware of the comparatively unreliable and unuseful legacies of non-science, anti-science, and pseudoscience.

Well, on second thoughts, there is one consequence that might concern you: Braininvat's life!

Remember I posed the challenge?:

Let's try an example. And let's make the stakes high to prevent flippant answers. An evil demon has taken one of us hostage, oh let's say BraininVat, and is holding a gun to his head. We're told:

"Scientific experts currently estimate the age of the Earth to be 4.5 billion years. You can choose to bet for or against this being the correct answer. I'm in a good mood so let's say I'll allow a margin of error of half a billion years on either side. Oh, by the way, I'm omniscient. If you bet wisely, this wretch goes free; otherwise he eats lead. Place your bets, please."

I'd bet against, and no, not because the experts are dumb. These things do tend to get revised a lot though.


Both Forest ("I'd take that bet. What do I have to lose?") and Braininvat ("I would bet the vat on 4.5 GY. There's just a shit-ton of good evidence.") seem confident that ours is the fortunate generation in which this "constant revision" in science has come to an end, at least with respect to the age of the Earth, or else that any subsequent revisions will remain safely within the margin of error our evil demon magnanimously permits.

I, for one, don't share their confidence: Newtonian mechanics was deemed infallible but turned out not to be, Maxwell enthused over the aether being the most highly confirmed (i.e., supported by a shit-ton of evidence) entity in all science, Feynman and Weinberg both warn us of the dangers of taking scientific knowledge to be certain, and I've little doubt that every other Tom, Dick and Harry who estimated the age of Earth, and got it hopelessly wrong, would also have appealed to "a shit-ton of good evidence".

Given you admit that science is subject to "constant revision", Lomax, how bet you, good sir?

[SciameriKen]

- I don't see how this has any particular consequence beyond a recognition that all experts should be treated as if they were mammals. It doesn't change the fact that some mammals are better informed than others. By all means we are constantly revising science; but let's be fair, and aware of the comparatively unreliable and unuseful legacies of non-science, anti-science, and pseudoscience.

Well, on second thoughts, there is one consequence that might concern you: Braininvat's life!

Remember I posed the challenge?:

Let's try an example. And let's make the stakes high to prevent flippant answers. An evil demon has taken one of us hostage, oh let's say BraininVat, and is holding a gun to his head. We're told:

"Scientific experts currently estimate the age of the Earth to be 4.5 billion years. You can choose to bet for or against this being the correct answer. I'm in a good mood so let's say I'll allow a margin of error of half a billion years on either side. Oh, by the way, I'm omniscient. If you bet wisely, this wretch goes free; otherwise he eats lead. Place your bets, please."

I'd bet against, and no, not because the experts are dumb. These things do tend to get revised a lot though.


Both Forest ("I'd take that bet. What do I have to lose?") and Braininvat ("I would bet the vat on 4.5 GY. There's just a shit-ton of good evidence.") seem confident that ours is the fortunate generation in which this "constant revision" in science has come to an end, at least with respect to the age of the Earth, or else that any subsequent revisions will remain safely within the margin of error our evil demon magnanimously permits.

I, for one, don't share their confidence: Newtonian mechanics was deemed infallible but turned out not to be, Maxwell enthused over the aether being the most highly confirmed (i.e., supported by a shit-ton of evidence) entity in all science, Feynman and Weinberg both warn us of the dangers of taking scientific knowledge to be certain, and I've little doubt that every other Tom, Dick and Harry who estimated the age of Earth, and got it hopelessly wrong, would also have appealed to "a shit-ton of good evidence".

Given you admit that science is subject to "constant revision", Lomax, how bet you, good sir?

No need to create dark scenarios such as this.

You avoided my previous question - but I'll post again - what is your larger point here? If its that we can't know everything 100% I"ll be largely unimpressed.

[NoShips]

You avoided my previous question - but I'll post again - what is your larger point here? If its that we can't know everything 100% I"ll be largely unimpressed.

I wasn't aware that knowledge, at least propositional knowledge (knowledge-that as opposed to knowledge-how) which is what we're examining here, admits of degrees.

It seems to me a person either knows a given proposition or does not know. How could you, for example, "70% know" that Paris is the capital of France, or that DNA has a double helix structure, or that the Earth is three weeks old?

Looks like you'll have to remain 90% unimpressed until we can figure out how a person could be 10% pregnant.


I think I sense what you mean to ask, though, and my answer is simply this: many people's confidence in scientific claims to knowledge is, in my opinion, incommensurate with the appropriate degree of epistemic weight we ought to assign to such claims.

Yes, I know it's very hard, when you're totally in the grip of a theory, to be skeptical of one's own research; after all, it really does seem that "the evidence is overwhelming". At times like these it's hard to be objective, stand back, and take into consideration the evidence from the historical record.

Perhaps the best remedy for this exaggerated confidence is a journey through the history and philosophy of science; books written by historians and philosophers of science rather than scientists themselves. After all, as Thomas Kuhn pointed out, "[sciences have] a persistent tendency to make [their] own history ... look linear and cumulative."


Two questions for you, Ken:

(i) How would you estimate the ratio of scientific hypotheses/theories ever proposed and once widely regarded as true only to be amended or abandoned vs those still regarded as true? 10:1? 1000:1? 100,000:1? Or what?

(ii) In light of your answer to (i), what do you feel is the appropriate degree of confidence we should assign to, say, the theory of evolution, as it stands right now, being true?