Egnor responds, falls flat on his face

| 266 Comments

The other day, the Time magazine blog strongly criticized the DI's list of irrelevant, unqualified scientists who "dissent from Darwin", and singled out a surgeon, Michael Egnor, as an example of the foolishness of the people who support the DI. I took apart some of Egnor's claims, that evolutionary processes can't generate new information. In particular, I showed that there are lots of publications that show new information emerging in organisms.

Egnor replied in a comment. He's still completely wrong. The Discovery Institute has posted his vapid comment, too, as if it says something, so let's briefly show where he has gone wrong.

Continue reading "Egnor responds, falls flat on his face" (on Pharyngula)

266 Comments

Now all Mr. Matzke has to do is demonstrate that these changes in the genome are the result of random, accidental, non-directed, fortuitous mutations and are not the result of intelligent guidance by structures and processes already programmed into the genetic machinery by an intelligent designer.

Sugarbear Wrote:

Now all Mr. Matzke has to do is demonstrate that these changes in the genome are the result of random, accidental, non-directed, fortuitous mutations and are not the result of intelligent guidance by structures and processes already programmed into the genetic machinery by an intelligent designer.

I will repeat what I told you over at my site (What is this? Are you going to waft about, spouting ignorant comments everywhere?)

WRONG. Those natural, non-directed mechanisms have been repeatedly demonstrated in the lab – they involve errors in the process of replication that are normal and to be expected. If someone wants to propose additional mechanisms, the onus is on them to demonstrate their reality. Have you got any evidence of any unusual intervention in any lineage on the planet? No? I’m not surprised. The IDists won’t even hypothesize a mechanism.

PZ wrote:

“Those natural, non-directed mechanisms have been repeatedly demonstrated in the lab — they involve errors in the process of replication that are normal and to be expected.”

Matzke cites a paper by Long et.al. that lists the various sources of new genes. They include exon shuffling, gene duplication, retroposition, transposable elements, lateral gene transfer, gene fusion/fission and coding regions arising de novo from non-coding regions. In looking at these various events it seems more likely to me that they are not at all random, accidental or non-directed. For example, when a retroposition occurs, it is the result of reverse transcription, not some arbitrary, accidental happenstance. Does retroposition occur independently of reverse transcription? I think not. In addition, transposable elements are directly recruited by host genes, not by any accidental, random or non-directed fortuitous event. I think that the preponderance of evidence favors the notion that at least some of these new genes are being created as a direct result of processes that are already embedded in the genome and are part of the intelligently designed machinery in the cell. While I cannot demonstrate empirically that these are intelligently guided processes, neither can you demonstrate that they are random, accidental or non-directed. But if I see trees lined up in an orchard in rows of 20 trees each, in perfect alignment what am I more likely to conclude, that they were the result of intelligent guidance or random chance?

If you see trees scattered seemingly haphazardly in a grove, would you argue that they were placed in their positions by chance or by the hand of a designer?

We don’t see everything “lined up…in perfect alignment”. We see accidents and happenstance arrangements throughout the genome. Yet you want to claim that the designer intended it that way, and clearly, no matter what arrangements were observed, you’d claim it was the product of intent.

Sugarbear — One day whilst walking in a temperate rain forest, I saw a little ‘plantation’ of about 4 rows of 4 trees each.

This was completely the result of natural processes: Long ago a tree fell over and decayed, becoming what is called a seed log in that tree seeds do much better starting on a decaying log. Some of these survived to grow tall. Those that did were well spaced along the former seed log, successfully competing for sunlight.

Then a storm, I surmise, blew about four of them over, regularly laid out. Each became a seed log in turn…

Voila, the plantation!

A similar pattern can be seen in fairy circles – rings of mushrooms that sprout around the edges of buried stumps of trees.

PZ wrote:

“Yet you want to claim that the designer intended it that way, and clearly, no matter what arrangements were observed, you’d claim it was the product of intent.”

And how are you different? You have already made up your mind that there is no intelligence involved and no matter what evidence is presented to you, you’d claim it was accidental. We differ, however in one significant way. My mind remains open to any possibilities while yours appears to be already made up and unwilling to be swayed by facts.

PZ wrote:

“A similar pattern can be seen in fairy circles — rings of mushrooms that sprout around the edges of buried stumps of trees.”

I picked the weakest of possible examples and you zeroed in on it. Surely it is not impossible to see patterns in nature that are random and accidental. But what if you went to the moon and saw a washing machine in one of the craters? Could you imagine that it arose by accident from materials on the moon’s surface?

Now all Mr. Matzke has to do is demonstrate that these changes in the genome are the result of random, accidental, non-directed, fortuitous mutations and are not the result of intelligent guidance by structures and processes already programmed into the genetic machinery by an intelligent designer.

Of course, despite the fact that science has done all this, by demonstrating how such changes in the genome are in fact purely natural, ID can always argue that it was designed.

Which is why Sober and others have rightfully concluded that ID is scientifically vacuous.

The difference between ID and real science is that the latter one is based on observations, data, research, logic, hypotheses, deductions and all that hard work that is typically required to do science. ID on the other hand rejects such hard work as ‘pathetic’.

OK, so show me the lunar washing machines.

I’m waiting.

I picked the weakest of possible examples and you zeroed in on it. Surely it is not impossible to see patterns in nature that are random and accidental. But what if you went to the moon and saw a washing machine in one of the craters? Could you imagine that it arose by accident from materials on the moon’s surface?

In other words, ID is scientifically vacuous because of the inevitability of false positives and the combination of a purely eliminative approach.

Fine, after we have laid that to rest, we can surely say that there is a spectrum of ‘design inferences’ and that ID does not provide us any tools to determine which is which. In fact, in case of DNA and evolution, there is no reason to accept a similarity with ‘design’ other than through the very poor and weakest form of ‘logic’ namely analogy. Analogy can be helpful in proposing hypotheses but ID does nothing more than ‘it looks like something we know was designed’ and thus ‘it must have been designed’. Fully begging the question.

Where is the hard work needed to determine if this analogy has any relevance?

And how are you different? You have already made up your mind that there is no intelligence involved and no matter what evidence is presented to you, you’d claim it was accidental. We differ, however in one significant way. My mind remains open to any possibilities while yours appears to be already made up and unwilling to be swayed by facts.

On the contrary, science is always open to intelligent involvement, which often rules out the ID movement. Do not hide behind being ‘open minded’ when in fact you are far less open minded than the real scientist.

It’s a sham my dear friend. If you were open minded, you would not be a mindless parrot for/of ID.

But what if you went to the moon and saw a washing machine in one of the craters? Could you imagine that it arose by accident from materials on the moon’s surface?

It’s funny how creationists pick examples of non-reproducing systems (not under evolutionary mechanisms) and then try to reason back to reproducing systems (which are subject to evolutionary mechanisms). Evolutionary mechanisms working on living systems allow for the accumulation of complexity over time, and can create complexity far beyond the capabilities of a human being. Complex systems like washing machines cannot accumulate complexity over time. All their complexity has to happen in one giant leap - leaving the only reasonable explanation to be “intelligent design”. Reasoning backwards from “complex organism” = “requires designer” is completely false.

“Fairy circles” of mushrooms aren’t the only circles in nature. Redwoods and sequoias also grow in circles, the vegetative offspring from the roots of a lone parent that’s long since disappeared. Is Sugarbear gonna say they’re intelligently designed too?

And if you look at the drum of a washing machine, it swirls in circles. Therefore, circular objects in nature are designed.

Also, the moon is circular as seen from earth when it is full, therefore the full moon is designed. Waxing, waning, half, and crescent moons may not be designed, or they may be the product of Satan.

I think Sugarbear needs to start contributing to Conservapedia.

Sugarbear Wrote:

In looking at these various events it seems more likely to me that they are not at all random, accidental or non-directed. For example, when a retroposition occurs, it is the result of reverse transcription, not some arbitrary, accidental happenstance.

When a raindrop falls, it is the result of condensation and gravity, not some arbitrary, accidental happenstance. Therefore, all rain is intelligently designed.

Does retroposition occur independently of reverse transcription? I think not. In addition, transposable elements are directly recruited by host genes, not by any accidental, random or non-directed fortuitous event.

Reverse transcription and recruitment are accidental, random, non-directed, whatever-else-you-want-to-call-it processes. We have no evidence that mobile elements are trying to bring useful genes along with them, nor that genes are trying to recruit useful nearby noncoding sequences. It just happens sometimes, and if it improves the organism’s fitness, it’s kept around.

And we know that retroposition often doesn’t do good things for fitness–it can be responsible for cancer, hemophilia, Huntington’s disease, Apert’s syndrome, etc. In fact, the effect is pretty…random.

I picked the weakest of possible examples and you zeroed in on it. Surely it is not impossible to see patterns in nature that are random and accidental. But what if you went to the moon and saw a washing machine in one of the craters? Could you imagine that it arose by accident from materials on the moon’s surface?

See, so far your examples have fallen into two categories–things that are seen in nature and are explained through unintelligent mechanisms; and things that wouldn’t be easily explainable that way but don’t actually exist.

This is the problem with ID. They can give us tornados in junkyards which assemble 747s, but those don’t happen…they can give us faces on Mars and streamside rocks with holes through the middle, but those have plausible explanations that don’t require nonhuman (let alone supernatural) intelligences. Something in the middle is what we need…a nonfictional occurrence which is also unexplainable without supernatural design.

Serious question: has any ID proponent ever bothered to use math to quantitatively show:

1. mutations add zero information.

2. “theoretical transformations” (which need not be plausible given a natural agent) by which information to the genome is added.

3. That a novel (or a change in) phenotype is impossible without this new information.

How in the world is all this talk of “information” relevant anyway? If one can show a known plausible, natural mechanism that leads to novel genes, surely that invalidates the applicability of any math theory that says it’s impossible.

Sugarbear writes…

But what if you went to the moon and saw a washing machine in one of the craters? Could you imagine that it arose by accident from materials on the moon’s surface?

Fine. I get your point.

We can all posit an unexplainable fact which would put a torpedo in the side of the SS Darwin. Is this conceptually possible? Yup, we all agree that it is, even Darwin agreed. In fact, he helpfully offered some avenues of exploration.

But the problem is that nobody ever has found the lunar washing machine; the inexplicable object that has no plausible explanation.

Mechanisms culling for selection — explained in the 1870s. Mechanisms allowing mutations — explained in the 1950s. The eye — explained. Several times for all the different models, in fact. Blood clotting — explained in the 80’s. Entropy arguments — debunked from the start. Information based arguments — ditto. The flagellum — plausible models developed last year. Etcetera, etcetera.

There just is no smoking gun.

After 150 years, now we’re arguing about tiny mechanisms inside the cell, because there’s nothing left.

Really, be honest, how likely is it that everything living thing on the earth was whipped up in an act of special creation, and yet it all looks exactly the way it would have if it evolved naturally, right down to all the myriad flaws?

Even Egnor has to concede the point…

Matzke cites a paper by Long et.al. that lists the various sources of new genes. They include exon shuffling, gene duplication, retroposition, transposable elements, lateral gene transfer, gene fusion/fission and coding regions arising de novo from non-coding regions.

And then, still feels that he just can’t accept what every single bit of physical evidence shows is possible…

.. it seems more likely to me that they are not at all random, accidental or non-directed. For example, when a retroposition occurs, it is the result of reverse transcription, not some arbitrary, accidental happenstance. Does retroposition occur independently of reverse transcription? I think not.

I’ve clipped viciously here, but you can reference his entire argument elsewhere.

It all comes down to “Can all this be explained by the simple laws of nature? Yes. But I’m going to disbelieve it anyway”.

While I cannot demonstrate empirically that these are intelligently guided processes, neither can you demonstrate that they are random, accidental or non-directed.

That’s the whole gist of the problem. Science can demonstrate that stuff “just happens”.

ID can demonstrate nothing other than a vague hope in some overarching meaning that mother nature simply doesn’t seem to give a fig about.

Look Sugarbear, I’m totally open to the idea of the existence of a designer of some sort that was involved in some biology. I mean, come on, that would be cool as shit. But to do this, we have to be able to distinguish design from mere apparent design, and no one has figured out a way to do that without knowledge of the designer.

Take archaeology. They make design inferences all the time. They see a piece of pottery, they conclude design. But they are only able to do this because they know a lot about the human designers, namely that we interact with reality in such a way that it is advantageous to have containers to fill with needed objects. Contrast this with SETI, which has yet to identify anything out there as “designed”. Now maybe that means there is nothing out there to find. Or maybe it means there is no way to detect design without knowing the designer. For all we know there an alien intelligence trying contact us right here, right now, but we just don’t recognize it.

The ID efforts on this have been far less than satisfactory. They toss about terms like “Specified Complexity”, despite the best efforts of mathematicians to attach objective meaning to it resulting in “Something with high information content that has low information content”. The IDers also keep parroting the “intelligence cannot arise from nonintelligence” mantra despite that happening in experiments with evolutionary algorithms all the time.

Want a Nobel prize? Figure out how to detect design and demonstrate it. You will have the respect and attention of the world, and the gratitude of many scientists.

Take archeology. One of the most difficult problems is distinguishing human-caused shapes from natural ones. Even something so obvious as ‘the remains of an ancient cookfire’ might actually have been caused by, say, a forest fire. Well-known archaeologists have been taken in by the similarity of rocks shaped by humans knapping and other natural processes.

Archeologists have, in recent decades, learned to be extremely cautious and careful in making design inferences.

Better, what if astronauts went to the Moon and brought back samples objects that had molds growing in them. How could that be interpreted as evidence of intelligent design? And shouldn’t it be even better evidence than a washing machine?

I only raise it because that’s what happened. One of the Apollo missions retrieved a camera put on the Moon earlier, and it was discovered upon return to Earth to have molds growing in it. The ID folks should be all over this one, since those hard-shell scientists have always “said” that life couldn’t survive in the harsh environs of the Moon, and so the only way it could have got there was by the Hand of God, right?

Except that it was a fairly standard mold which is known to plague camera factories. A simpler solution is that the mold contaminated the camera prior to its leaving Earth, and that contrary to previous hypothesis, molds can survive on the Moon.

If we found a washing machine on the Moon, we’d look around to see what human put it there, and how.

Creationists, it appears, are not rocket scientists, either.

Sugarbear Wrote:

if I see trees lined up in an orchard in rows of 20 trees each, in perfect alignment what am I more likely to conclude, that they were the result of intelligent guidance or random chance?

That’s an extremely weak argument. Crystals contain billions upon billions of atoms in perfect alignment. They are nonetheless the result of a purely natural process involving a great deal of randomness.

In looking at these various events it seems more likely to me that they are not at all random, accidental or non-directed.

…and this projection of subjective perception applied to observation (better known as “gut instinct”) is exactly what keeps the rubes coming to the ID church.

who the f*ck cares what it “seems” like to you? the world seems flat to my eyes. doesn’t mean it is.

that’s why we actually investigate what really IS going on, when perception alone isn’t sufficient.

that’s part of science; something the IDiots have obviously never known, nor apparently care to.

I’m surprised nobody’s recognized the tedious crank behind Sugarbear.

Give you a hint. Google “random, accidental, non-directed, fortuitous mutations”.

Crap. Wagner. That idiot and fraud.

Never mind, I won’t be wasting my time with him any more.

LOL

So much for attesting to the power of the mind and design, when charlie can’t even make up new phrases to disguise his identity.

PZ wrote:

“Crap. Wagner. That idiot and fraud.

Never mind, I won’t be wasting my time with him any more.”

It’s hard to disguise true genius. But it took you long enough to figure it out. ;-) You may not have to put up with me much longer. I’m flying to New York tomorrow to have a 5.6 cm aneurysm removed from my aorta. Say a prayer for me, will you?

It’s easy to recognize Charlie from his poor technique. He strings together too many adjectives, for one thing.

Uh-oh

The Overwhelmingly Stupids are at it again. This time they are claiming that PZ Myers is bullying the Doctor for criticizing his arguments.

http://www.overwhelmingevidence.com[…]om_darwinism

Say a prayer for me, will you?

no, but I’ll break out my tiny violin for you, how’s that?

All through history, in all human cultures, so-called supernatural events have been experienced. I think the word “supernatural” is misleading. The events are perfectly natural, just not yet understood by modern science.

That’s right, they are only “so-called” supernatural, “supernatural” is misleading, all events are perfectly natural (and many of them are understood by science). Now go tell that to Dembski and Behe and the rest of the IDiots. Oh, but wait, you wrote “ID is a grave threat because, if proven, it would undermine scientific materialism”, and you think that “ID seems the obvious answer”. So you’ve contradicted yourself, indicating that you’re confused or dishonest or trolling or some combination. In any case, you’re a waste of time and energy.

you don’t need accurate timekeeping to confirm that two fast-moving objects hit the ground simultaneously? Huh.

No, Anton, you don’t. As Galileo observed in his notebook, an object consisting of two objects tied together hits the ground at the same time as the lighter objects comprising it, and a light object tied to a heavy object either falls just a fast or retards the heavier object, resulting in the combined (heavier) object falling slower, which is a contradiction. Having carried out this thought experiment, he had no need to carry out a physical experiment, and may not have – see A.F. Chalmers’ “What is this thing called Science?” for further discussion.

Which is not to say that Clouser isn’t a loon and didn’t make numerous ridiculous claims about Aristotle.

Carol, the comedienne:

they viewed phenomena as the result of the actions of batttling gods

Did they get really teed off in that battle?

Or was that a clever-beyond-measure visual reference to the three crosses ==> trinity, like the verbal pun you tried earlier?

Any better guesses? A free, piping-hot pizza, delivered virtually instantaneously, dressed to suit, awaits the funniest* explanation.

*(That Carol can’t spell doesn’t count. That we know.)

clouser: Modern science is the antithesis of Greek logic and to say otherwise is just plain ignorance. It was Greek logic that led Aristotle to the logical conclusion that heavier objects reach the ground before lighter ones, that the closer an object gets to the ground the heavier it gets, and many other such insightful statements.

Why are you conflating Greek logic with Greek science and conflating Aristotle with all Greek science. The Greeks were quite in love with logic but they weren’t limited to it and it alone. There were many more Greek scientists that just Aristotle and they originated the experimental tradition rediscovered and exemplified by Galileo. Many Greeks did experimental science in modern sense. Their limitations were technological not philosophical.

clouser:that the closer an object gets to the ground the heavier it gets

Regardless of how Aristotle arrived at this conclusion it is, atleast, a true statement, to the degree that closer to the ground is closer to the center of the earth.

clouser: (2) Many of the ancient polytheistic Greeks were really modern scientists, despite the fact that they viewed phenomena as the result of the actions of batttling gods.

WRONG, WRONG, WRONG, WRONG, AND MORE WRONG ! ! ! The entire point of the Greek awakening was that they rejected gods as any kind of answer to the questions they were asking about the world they lived in. I have read any number of explanations about this but Sagan said it better than i can.

The first Ionian scientist was Thales of Miletus, a city in Asia across a narrow channel of water from the island of Samos. He had traveled in Egypt and was conversant with the knowledge of Babylon. … Thales attempted to understand the world without invoking the intervention of the gods. Like the Babylonians, he believed the world to have once been water. To explain the dry land, the Babylonians added that Marduk had placed a mat on the face of the waters and piled dirt upon it. Thales held a similar view, but, as Benjamin Farrington said, ‘left Marduk out.’ Yes, everything was once water, but the Earth formed out of the oceans by a natural process-similar, he thought, to the silting he had observed at the delta of the Nile. Indeed, he thought that water was a common principle underlying all of matter, just as today we might say the same of electrons, protons and neutrons, or of quarks. Whether Thales’ conclusion was correct is not as important as his approach: The world was not made by the gods, but instead was the work of material forces interacting in Nature. Thales brought back from Babylon and Egypt the seeds of the new sciences of astronomy and geometry, sciences that would sprout and grow in the fertile soil of Ionia. (Carl Sagan, “Cosmos”, ch VII “The Backbone of Night”, pages 176-177)

I would have liked to type the whole section but six pages of text was too much. The pertinent section begins on page 174.

Carol you seem so enamored of monotheism but I would ask; how many gods were worshiped by the religion that crushed the Greek awakening?

I believe it’s now safe to say,declare that whatever one responds to Carol,no general difference will be Observed. Except in the diverse and huge energy used and consumed in order to answer (in vain) to her chaotic thoughts. If you scroll up this thread you’ll see that She,Carol, has been my Muse,forcing extensive and unused parts of my brain to stop being lazy. Therefore ,she is going herefrom ,to be called by me, Aerologias Hanassa or Mousa Moy.

forgive me Mousa Moy,I meant Aerologias Anassa or Vanassa

Paul,

Hi. Haven’t seen you here for quite some time. But you didn’t miss much.

Most of your comments actually support my position. Read through the thread carefully and you will see that your remarks are best addressed to the other commenters, my interlocutors, here.

But a few points are in order:

(1) Aristotle is mentioned because he stands out as one of the highest achieving Greek intellectuals.

(2) The Greeks did observe and discover, but when it came to postulating laws or finding patterns they typically resorted to philosophy.

(3) Unfortunately, their laudable work (where it was so) did not lay the foundation for modern science that is systemic, continuous and that animates others to build upon previous work, as is evident from the fact that no work at all took place for centuries. I know the blame for this lies elsewhere, but it is the fact nonetheless.

(4) Yes, as an object approaches the ground there is an indetectable, vanishingly small increase in the force of gravity upon it (due to the inverse square law), but according to Aristotle this increase must be much more pronounced to explain the very noticeable increase in speed of the falling object.

(5) I agree that many of the Greeks engaged in observation and discovery were not polytheists. You should direct your comments in this regard to the other commenters here.

Carol, do you ever get tired of making a fool of yourself in public?

(2) The Greeks did observe and discover, but when it came to postulating laws or finding patterns they typically resorted to philosophy.

Yes, the Greeks invented the term “philosophy” to mean “pursuit of knowledge,” of which “postulating laws or finding patterns” was, and is, an integral part. This certainly does nothing to advance your original thesis, which was, let’s remember, that polytheists didn’t do that sort of thing at all.

(3) Unfortunately, their laudable work (where it was so) did not lay the foundation for modern science that is systemic, continuous and that animates others to build upon previous work, as is evident from the fact that no work at all took place for centuries…

Their work was animating plenty of people to build on it, until a certain coalition of monotheists snuffed it out with all the force at their disposal. Just because it was forcibly stopped, does not make it meaningless, especially after it was restarted.

…I know the blame for this lies elsewhere, but it is the fact nonetheless.

Thank you, you have just undercut your own thesis without even knowing it. Where, exactly, do you “know” the blame lies?

Heck, I’ll give the virtual pizza contest a shot (if only out of the vain hope of partially repairing my longstanding breach with LPG…):

Carol has obvious issues with poly-t-ism.

Surely somebody can do better than that!

Most of your comments actually support my position.

of course they do, Carol.

of course they do.

(psst: project much?)

It’s amusing that Carol first wrote “The eventual spread of monotheism laid the philosophical foundation for the future sea-change in human thinking, that events are ordered instead of chaotic, and thereby created the basis for science”, but is now complaining that the Greeks “typically resorted to philosophy”. But then, Carol is always amusing.

Paul Flocken asked “how many gods were worshiped by the religion that crushed the Greek awakening?” Interesting point. It’s arguable that the awakening was mortally wounded, if not actually crushed, by Ptolemy VIII around 145BC, for reasons unconnected with religion. It’s subsequent decline may have been more a matter of neglect by later Roman overlords than religious antipathy. Not sure either whether it’s sensible to generalise about the early Christian Church’s attitude towards whatever science there was at the time. Can find examples of extreme hostility (although again the notorious murder of Hypatia may have been more for political than religious reasons), of realism (that passage from St Augustine that’s always being quoted) and no doubt many shades in between. Not so different from today really.

Hipparchus, 190 BCE – 120 BCE was the first to correctly predict solar eclipses.

Three centuries later, the astronomer Ptolemy build on his work to form the epicyclic model.

Hmmm, doesn’t appear to be crushed or anything, just infrequent advances since there were so few scientists in those days…

One might suppose that the Greeks who produced much of the foundation of science were moving toward monotheism, if one looked just at Plato. When we look at Aristotle (his god is decidedly unorthodox and unlike the gods of the monotheists) and other later thinkers, however, the monotheistic tendencies appear much more like a movement away from religion altogether.

The atomists of the Epicurean school, in particular, seem to be leaving religion behind, though not entirely behind. Lucretius, etc., have all of the appearances of being close to modern science in thought, although they lack too much of the facts of science to be able to do much with their admirable outlook.

For what little it’s worth, Dembski has sometimes tried to suggest that we “Darwinists” are adherents of Epicurean philosophy, rather than acknowledging the fact that sense tends to drive ancients and moderns toward the same stance. I’d give him just one thing, which is that Epicureanism probably did set a useful precedent for those who preferred thinking from nature to model, rather than trying to impose models on the facts about nature.

Monotheism may be thought to have had a salutary effect upon science once it was revived, mainly by driving the effects of the gods away from the terrestrial sphere. In a sense it is true that monotheism may well be a step on the road to empirical thought, the diminishment of the role of the gods that is completed when people give up the last one. Of course I’m not saying that the last one has to be relinquished to do good science, just that believing that “the gods”, or even Aristotelian tendencies of objects, cause what we see does not assist in doing science.

Gav points to the loss of interest in science during the Roman Empire, something that is not especially well explained. Epicureanism didn’t die out very quickly, however, with Lucretius writing in the 1st century BC, and Epicurean writings having been found to make up a considerable portion of a library found at either Pompey or Herculaneum (as I recall it was the latter). That Epicureanism was a dead end without more empirical facts being produced (Epicureans evidently didn’t do a whole lot of science) may have led to its eventual eclipse in favor of more mystical philosophies, especially if issues of the afterlife might have seemed more important than improving machines and science in the face of disintegrating empire.

To the extent that monotheism might help science along it appears to be doing partially what secularism does all the better, it denies proximal causes by invisible deities, and suggests unity of the world and its forces. If one wishes to praise monotheism as a stepping stone away from religious explanations and toward physics pure and simple (which understands the universe as a unity, but also as operating sans theistic causation), well and good.

But it was the Greeks, who were successful in laying much of the basis of science in so far as they denied action by invisible minds, who were most instrumental in fashioning a view of the universe as a unity, not the monotheists who attributed any observed unity to the outside force of a God. Later monotheists were able to take in the philosophies of the Greeks in part because the Greek thinkers weren’t polytheists, yet these monotheists were successful by following the Greeks away from an instrumental view of religion, not because monotheism per se leads toward science.

Glen D http://tinyurl.com/35s39o

Popper's ghost Wrote:

No, Anton, you don’t. As Galileo observed in his notebook, an object consisting of two objects tied together hits the ground at the same time as the lighter objects comprising it, and a light object tied to a heavy object either falls just a fast or retards the heavier object, resulting in the combined (heavier) object falling slower, which is a contradiction.

Well, two things there. The notion of the lighter object retarding the heavier one doesn’t seem (at least to me) to be immediately obvious without some experimentally-derived understanding of force and tension–which latter Galileo studied, not coincidentally. And while the thought experiment may point out the absurdity of gravitational acceleration depending purely on weight, it doesn’t prove that gravitational acceleration is independent of weight. Indeed, you could envision the same experiment with air resistance factored in, and of course acceleration would be influenced by weight then. Likewise for objects being accelerated by, say, an electromagnetic field.

Having carried out this thought experiment, he had no need to carry out a physical experiment, and may not have — see A.F. Chalmers’ “What is this thing called Science?” for further discussion.

I’ve never read Chalmers, but from Google Scholar there seem to be a lot of recent articles arguing that Galileo did perform the experiments he described–something about a new journal of his having been discovered?

Though it would be very ironic if he overturned Aristotle’s mildly observation-based theory of gravity by means of a thought experiment.…

The notion of the lighter object retarding the heavier one doesn’t seem (at least to me) to be immediately obvious without some experimentally-derived understanding of force and tension—which latter Galileo studied, not coincidentally. And while the thought experiment may point out the absurdity of gravitational acceleration depending purely on weight, it doesn’t prove that gravitational acceleration is independent of weight. Indeed, you could envision the same experiment with air resistance factored in, and of course acceleration would be influenced by weight then. Likewise for objects being accelerated by, say, an electromagnetic field.

You’re making things unnecessarily complicated. I realized several years ago, before learning of Galileo’s thought experiments, that it follows logically from the fact that half an object falls at the same rate as the whole object that a heavier object doesn’t necessarily fall faster than a lighter object, thereby refuting Aristotle. What would you expect upon dropping two cannonballs, one of which has been split in half and the other hasn’t? Why should the separated halves fall slower than the attached halves? Perhaps they would, but there is no reason to expect it – Aristotle’s claim now seems rather unintuitive.

Here is a discussion of Galileo’s “famous” thought experiment. Looking at Chalmers, I can’t find (via the index) mention of this thought experiment, although he does write

Contrary to the popular myth, Galileo seems to have performed few experiments. Many of the “experiments” he refers to while articulating his theory are thought experiments. This is a paradoxical fact for those empiricists who think that new theories are derived from the facts in some way, but it is quite comprehensible when it is realized that precise experimentation can only be carried out if one has a precise theory capable of yielding predictions in the form of precise observation statements. Galileo was in the process of making a major contribution to the building of a new mechanics that was to prove capable of supporting detailed experimentation at a later stage. It need not be surprising that his efforts involved thought experiments, analogies and illustrative metaphors rather than detailed experimentation.

—–

from Google Scholar there seem to be a lot of recent articles arguing that Galileo did perform the experiments he described—something about a new journal of his having been discovered?

That may be, but his journals nonetheless describe many thought experiments, including the one about falling bodies – try entering Galileo thought experient.

er, Galileo thought experiment

Here’s another thought experiment: coat a lighter object and a heavier object with superglue, and drop the heavier object just after the lighter object. According to Aristotle, when the heavier object catches up with the lighter object and bonds to it, it will suddenly accelerate. The thought experiment indicates that Aristotle’s conception of speed is flawed.

As I said Anton, in response to your question “you don’t need accurate timekeeping to confirm that two fast-moving objects hit the ground simultaneously?”, Galileo having carried out his thought experiment had no need to carry out a physical experiment. Perhaps he did, but he already had logical confirmation, and had his timekeeping equipment indicated otherwise, he would have had good reason to question its accuracy.

For those not old enough to remember the famous Apollo 15 TV clip.

The Apollo 15 Hammer-Feather Drop.

Movie link: http://nssdc.gsfc.nasa.gov/planetar[…]op_sound.mov

Popper's Ghost Wrote:

You’re making things unnecessarily complicated. I realized several years ago, before learning of Galileo’s thought experiments, that it follows logically from the fact that half an object falls at the same rate as the whole object that a heavier object doesn’t necessarily fall faster than a lighter object, thereby refuting Aristotle. What would you expect upon dropping two cannonballs, one of which has been split in half and the other hasn’t? Why should the separated halves fall slower than the attached halves? Perhaps they would, but there is no reason to expect it — Aristotle’s claim now seems rather unintuitive.

And yet they do fall slower. Moreover, if you grind the cannonball into iron filings, you find–unsurprisingly–that the cloud of filings drops considerably more slowly than the entire ball. A cloud of dust falls more slowly than an equal-weight dirt clod. If you understand air resistance you see why those examples don’t really count, but if you don’t, I’d say intuition falls closer to the Aristotelian model than the Galilean.

That may be, but his journals nonetheless describe many thought experiments, including the one about falling bodies — try entering Galileo thought experient.

Oh, I agree. So far as I know, he did test balls rolling down inclined planes, and (due to friction, I imagine), found results only partly in agreement with his theory–and he just didn’t bother talking about the failures! See “The Pendulum Swings Again: A Mathematical Reassessment of Galileo’s Experiments with Inclined Planes” by Alexander J. Hahn, in Arch. Hist. Exact Sci. 56 (2002).

Here’s another thought experiment: coat a lighter object and a heavier object with superglue, and drop the heavier object just after the lighter object. According to Aristotle, when the heavier object catches up with the lighter object and bonds to it, it will suddenly accelerate. The thought experiment indicates that Aristotle’s conception of speed is flawed.

Except that Aristotle would generally be correct there. (Depends on exactly how each object is shaped, but if they’re, say, hemispheres of equal size but different density, they will suddenly accelerate once they’re touching. You don’t even need glue.)

Aristotle would still be quantitatively incorrect, of course, since the various objects don’t fall with accelerations proportional to their weights.

As I said Anton, in response to your question “you don’t need accurate timekeeping to confirm that two fast-moving objects hit the ground simultaneously?”, Galileo having carried out his thought experiment had no need to carry out a physical experiment. Perhaps he did, but he already had logical confirmation, and had his timekeeping equipment indicated otherwise, he would have had good reason to question its accuracy.

But if his timekeeping was sufficiently accurate, it would indicate otherwise. You may be quite right that Galileo didn’t feel the need to check up on his claim, but we now know that it’s simply not true unless you’re in a vacuum. No thought experiment can logically confirm a claim that’s false.

Not friction (unless you mean air resistance), rotational inertia. You’ve got to get the ball started, after all :)

W. Kevin Vicklund Wrote:

Not friction (unless you mean air resistance), rotational inertia. You’ve got to get the ball started, after all :)

Actually, I did mean friction: air resistance plus the possibility of the ball skidding slightly rather than purely rolling. It’s been a long time since any mechanics classes, but IIRC two rolling balls of equal radius but different mass should–barring friction–move identically on an inclined plane. Rotational inertia slows them both down vs. falling or sliding balls, but it’s still proportional to mass so it doesn’t screw up the uniformity of their acceleration.

Not that Galileo knew that. But that alone shouldn’t have messed up his results AFAIK.

And yet they do fall slower.

Even if you were correct, Galileo didn’t think so, which is what is relevant. But you aren’t correct, as there are configurations, such as a cannonball that has been sliced horizontally, where air resistance is identical.

If you understand air resistance you see why those examples don’t really count, but if you don’t, I’d say intuition falls closer to the Aristotelian model than the Galilean.

Since Aristotle’s intuition doesn’t involve air resistance, that can’t be right. As you say, his intuition was that objects fall with accelerations proportional to their weights, and that intuition is starkly wrong.

But if his timekeeping was sufficiently accurate, it would indicate otherwise. You may be quite right that Galileo didn’t feel the need to check up on his claim, but we now know that it’s simply not true unless you’re in a vacuum. No thought experiment can logically confirm a claim that’s false.

Ah, so you are arguing that Galileo must not have actually carried out the experiment, because if he had he would have observed that Aristotle was qualitatively right? That’s remarkably inconsistent with “you don’t need accurate timekeeping to confirm that two fast-moving objects hit the ground simultaneously? Huh.”

You comments about “intuition fall[ing] closer to the Aristotelian model” and “Aristotle would generally be correct there” are also remarkably inconsistent with “it would be very ironic if he overturned Aristotle’s mildly observation-based theory of gravity by means of a thought experiment”, as it seems to imply that one would naturally assume that it was physical experiment, thought experiment, that had that result.

Popper's ghost Wrote:

And yet they do fall slower.

Even if you were correct, Galileo didn’t think so, which is what is relevant. But you aren’t correct, as there are configurations, such as a cannonball that has been sliced horizontally, where air resistance is identical.

If the air resistance is identical to the whole-cannonball case, then the halves will fall slower, because they’re each experiencing the same retarding force versus only half of the original gravitational force, as acting on half the original mass. The halves will fall at the same speed as the whole cannon ball only if the air resistance they each experience at a given speed is also cut in half. This isn’t actually possible–even if you slice the cannonball vertically, so its horizontal cross-sectional area is halved, the drag from skin friction will still be more than half its original value.

I suppose if the ball is sliced horizontally and the halves are left in contact, and the distance dropped is small, the halves might not have time to come apart at all and experience significantly increased drag. But only shows that halves which are combined into one object fall faster than separated halves, which, again, is qualitatively in line with Aristotle.

And no, what Galileo thinks isn’t the issue. You were saying that your intuition agreed with him; I was saying that mine doesn’t.

If you understand air resistance you see why those examples don’t really count, but if you don’t, I’d say intuition falls closer to the Aristotelian model than the Galilean.

Since Aristotle’s intuition doesn’t involve air resistance, that can’t be right. As you say, his intuition was that objects fall with accelerations proportional to their weights, and that intuition is starkly wrong.

I don’t know what Aristotle’s intuition was, although I’m fairly confident he thought he was basing his model of physics on logic and observation, not intuition. But his model is all about resistance–his whole idea is that a moving (earthly) object’s natural tendency is to come to rest. Moreover, in De Caelo he explicitly invokes resistance to motion through a medium to explain why objects with a wide cross-section fall or rise more slowly:

“The shape of bodies will not account for their moving upward or downward in general, though it will account for their moving faster or slower. The reasons for this are not difficult to see. For the problem thus raised is why a flat piece of iron or lead floats upon water, while smaller and less heavy things, so long as they are round or long-a needle, for instance-sink down; and sometimes a thing floats because it is small, as with gold dust and the various earthy and dusty materials which throng the air. With regard to these questions, it is wrong to accept the explanation offered by Democritus. He says that the warm bodies moving up out of the water hold up heavy bodies which are broad, while the narrow ones fall through, because the bodies which offer this resistance are not numerous. But this would be even more likely to happen in air-an objection which he himself raises. His reply to the objection is feeble. In the air, he says, the ‘drive’ (meaning by drive the movement of the upward moving bodies) is not uniform in direction. But since some continua are easily divided and others less easily, and things which produce division differ similarly in the case with which they produce it, the explanation must be found in this fact. It is the easily bounded, in proportion as it is easily bounded, which is easily divided; and air is more so than water, water than earth. Further, the smaller the quantity in each kind, the more easily it is divided and disrupted. Thus the reason why broad things keep their place is because they cover so wide a surface and the greater quantity is less easily disrupted. Bodies of the opposite shape sink down because they occupy so little of the surface, which is therefore easily parted. And these considerations apply with far greater force to air, since it is so much more easily divided than water. But since there are two factors, the force responsible for the downward motion of the heavy body and the disruption-resisting force of the continuous surface, there must be some ratio between the two. For in proportion as the force applied by the heavy thing towards disruption and division exceeds that which resides in the continuum, the quicker will it force its way down; only if the force of the heavy thing is the weaker, will it ride upon the surface.”

Aristotle essentially envisions a friction-dominated world, just as Galileo envisions a frictionless one. Both are quantitatively wrong; but each view is qualitatively correct under certain conditions.

But if his timekeeping was sufficiently accurate, it would indicate otherwise. You may be quite right that Galileo didn’t feel the need to check up on his claim, but we now know that it’s simply not true unless you’re in a vacuum. No thought experiment can logically confirm a claim that’s false.

Ah, so you are arguing that Galileo must not have actually carried out the experiment, because if he had he would have observed that Aristotle was qualitatively right?

No, I earlier cited a paper arguing that he had carried out at least three such experiments, but discarded some of his results precisely because Aristotle was qualitatively right, and friction produced results inconsistent with Galileo’s predictions.

That’s remarkably inconsistent with “you don’t need accurate timekeeping to confirm that two fast-moving objects hit the ground simultaneously? Huh.”

Um, the two statements don’t have anything to do with each other. Two objects dropped simultaneously from the same height don’t in general hit the ground simultaneously. But if they did, you’d need accurate timekeeping to confirm it. Do you see now?

You comments about “intuition fall[ing] closer to the Aristotelian model” and “Aristotle would generally be correct there” are also remarkably inconsistent with “it would be very ironic if he overturned Aristotle’s mildly observation-based theory of gravity by means of a thought experiment”, as it seems to imply that one would naturally assume that it was physical experiment, thought experiment, that had that result.

I don’t know that means. Are you equating physical experiments and thought experiments?

Let me try again. The standard story, as repeated by Carol, is that Aristotle developed his theory of gravity by means of pure philosophy and logic, and that Galileo refuted it by means of physical experiment and empirical observation. It would be very ironic if, in fact, Aristotle’s theory owed more to observation and Galileo’s refutation was based primarily on thought experiments.

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This page contains a single entry by PZ Myers published on February 24, 2007 10:55 AM.

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