January 20, 2002 | David F. Coppedge

Reality or Hubris in Scientific Claims?

51; The amount of trust the public puts in scientific claims stems partly from their incomprehensibility.  The claims presented in scientific papers are often so dense and abstruse as to be unapproachable by all but specialists.  Undoubtedly many people trust scientists because of their specialized education, their knowledge of mathematics, their special equipment, and their use of the “scientific method” (however that is defined) that is assumed to lead to reliable knowledge.  The popular press tries to condense and explain scientific explanations in plain English, but at the risk of oversimplifying, editorializing, misinterpreting, misconstruing or hyping the evidence.  At times, though, claims by scientists seem so beyond experience that it is right to at least ask how can they be empirically justified.  Some recent examples might serve to illustrate the problem.

  1. Galaxy evolution:  Nobody has seen dark matter, and nobody has watched a galaxy rotate once, let alone form and evolve.  Yet several recent articles, like one on Space.com, claim that astronomers have “solved” the mysteries behind galaxy shapes.  “Now scientists have used dark matter theory to predict the menagerie of galaxies found in the universe,” Clara Moskowitz wrote triumphantly.  “Their new model reproduces 13 billion years’ worth of cosmic evolution, resulting in a surprisingly accurate tally of the different kinds of galaxies we see.”  An astute observer might ask if they confirmed reality, or just confirmed their artificial model.  Even when a model reproduces observations, that does not justify it.  The fallacy of affirming the consequent (i.e., after the prediction, therefore because of the prediction) lurks to undermine any prediction – as does the problem of underdetermination of theories by data (i.e., there are always multiple theories that can account for the same data).  Doubts should escalate when copious amounts of occult factors or unobservables (like dark matter) are thrown into a model to make it work.  None of these concerns disprove the theory presented in this article, but should turn on caution blinkers on the victory lap.
  2. Galaxy formation:  A similar air of triumph was evident in Science Daily’s article titled, “How Galaxies Form: New Research Resolves Conflict in Theory.”  The supercomputers used in this study are indeed impressive – they ran the equivalent of 100 years of simulations.  But the same problems noted above (occult factors like cold dark matter, logical fallacies) plague this article.  We are told that “The cold dark matter theory works amazingly well at telling where, when and how many galaxies should form.”  The new simulation apparently showed them that massive early stars in dwarf galaxies would produce such explosive supernovae that they would starve the cores of material for star formation, and this is said to match observations of dwarf galaxies.  To make the simulation work, though, they had to invoke the assumption that 75% of reality is unobservable.  “In the cold dark matter theory, smaller structures form first, then they merge with each other to form more massive halos, and finally galaxies form within the halos.”  Nobody knows what cold dark matter is; it serves as a placeholder for ignorance in certain theories.
  3. Thinking germs:  “Bacteria Are More Capable of Complex Decision-Making Than Thought,” announced a strange article in Science Daily that tells us that scientists are learning how bacteria “think.”  Is this merely a little justifiable anthropomorphism for pedagogical purposes, or does it mislead?  “We see now that bacteria are, in their way, big thinkers, and by knowing how they ‘feel’ about the environment around them, we can look at new and different ways to work with them.”  The article is about stimulus and response, not thinking as humans use the term.  An argument could be made that this is more distraction than education.
  4. Dusty message:  It sounds like a headline from the National Enquirer: “Alien Dust Kicked Up By Baby Planet Collisions.”  Andrea Thompson at Live Science tendered the usual confidence in a theory with some surprise and mystery: a ring around a star has “alien dust” that theory did not predict for the terrestrial planet zone.  A story was not long in coming: “The cooler dust likely did not result from planetary collisions, and is instead probably the leftovers of planet formation that took place farther away from the sun,” an astronomer from UCLA explained to the American Astronomical Society.  He even threw in a little SETI: “These stars aren’t good targets in the hunt for extraterrestrials.”  He knows that because the parent stars are short-lived and windy, and as we all know, it takes billions of years for sentient beings to evolve from chemicals.  It appears that ignorance of key points in the observations is not a deterrent for promoting stories in the press.
  5. Message from the mantle:  We are receiving messages from deep inside the earth from crystals.  That’s what Science Daily tells us in an article headlined, “Zircons and Their Message from the Earth’s Mantle.”  Lest you think that scientists journeyed to the interior of the earth and interviewed say, Mickey Mantle, and learned the zircon language of the creatures of the deep, the triumphant announcement seems tenuous at best.  The article appeals to millions of unexperienced years.  The lines between theory, belief and fact seem so blurred as to evaporate.  We know we can measure melting points in the lab, and current radioactive decay rates, and locations of zircons on the surface, but what are we to make of stories about how where they came from and how they got to their discovery sites on the surface?  “Their results show that these zircons were formed in the Earth mantle and were stored in this environment many million of years before they were delivered to the surface by basalt lava flows with which they are associated,” the article stated in an almost comforting certainty.  “…Zircons like these, apart from their aesthetic beauty, carry a wealth of information and offer an interesting glimpse in the mantle.”
  6. Older Sierras:  The Sierra Nevada mountains of California are older than previously thought, PhysOrg tells us.  On what basis did scientists at Yale and Berkeley arrive at that conclusion?  The evidence consisted of “50-million-year-old chemical traces left by microbes and rain droplets that fell onto ancient leaves to calculate the new height estimate for the Sierras at that time.”  The article did not explain how, without having watched the leaves and timed those years with a stopwatch, the scientists could know the starting conditions of the leaves and what they subsequently experienced in a vast amount of time, during which who-knows-what environmental changes could have altered the evidence.  Nor did they explain how rain drops on leaves reliably correlate to the height of a mountain chain, without taking into account unlisted variables like climate, atmospheric concentration, and rates of uplift.  These doubts were simply swept aside in the confident conclusion, “It’s amazing to break open a rock and look at these amazingly preserved leaves that can tell you a story from 50 million years ago.”
  7. Cave crystal ball:  Now we know that a cave in Arizona responded to a wet Greenland 55,000 years ago, PhysOrg announced.  How?  Julia Cole of the University of Arizona measured detailed structures of a stalactite and figured it all out.  “These changes are part of a global pattern of abrupt changes that were first documented in Greenland ice cores,” she said.  “No one had documented those changes in the Southwest before.”  She measured samples of oxygen-18 in razor thin samples of the stalactite.  She used uranium-thorium dating.  She claims to have found correlations with Greenland ice cores: “When it was cold in Greenland, it was wet here, and when it was warm in Greenland, it was dry here.”  Indeed, “The stalagmite yielded an almost continuous, century-by-century climate record spanning 55,000 to 11,000 years ago.”  What was unstated were the assumptions behind the dating methods (including confidence in climate models and controversial temperature proxies), other possible explanations for the patterns due to underdetermination of theories by data, the risk of extrapolation from current stalactite growth rates, the use of proxies for unexperienced years in lieu of strict empiricism, possible flaws in the methods of calibration and assumptions underlying them, possible confusion of cause and effect, and possible human contamination of the cave environment, among other issues.  But how could any layman avoid falling under the spell of a siren song like this?  “By matching the stalagmite’s growth timeline with the sequence of wet and dry periods revealed by the oxygen analyses, the researchers could tell in century-by-century detail when the Southwest was wet and when it was dry.”

Science grew under the leadership of bold men and women who learned to question authority, to doubt, and to prove rigorously with observational evidence – not just ancillary data points that fit a preconceived story or model, but with decisive empirical evidence that was testable without reliance on auxiliary hypotheses and occult phenomena.  Nowadays, it seems that most readers of science are content to let the authorities tell us what to believe.

Scientific explanations today frequently go far, far beyond any empirical data.  They make inferences that can scarcely be justified.  If the kinds of inferences made by scientists were made by any other scholars, people would call them nuts.  Yet scientists get away with it, because they have achieved the kind of presumptive authority that medieval scholars had.  The success of science feeds on itself.  Like a rich corporation buying up the real estate in the city, science enlarges its territory and takes over.  Citizens watch and hope that it means progress.
    You may have been taught that science restricts itself to empirical evidence.  That may have been true in the 18th century, but increasingly, scientists, like gluttons, feel they can devour any subject with impunity.  Empirical modesty has been replaced by epistemological ambition.  It’s no longer “We will restrict ourselves to what we can measure,” but “We will explain all of reality!”  If these scientists really restricted themselves to the evidence, their stories would be far less interesting.  Here’s how strict empiricists might report their findings.

  1. Galaxy evolution:  We catalogued different shapes of galaxies.  We turned on a computer and it powered up.
  2. Galaxy formation:  We ran a program on a supercomputer for the equivalent of 100 years of processing, and found that globs of graphical matter interacted the way we programmed them to.
  3. Thinking germs:  We watched receptors on the membranes of bacteria react to the presence of nitrogen.  They reacted differently in the presence of oxygen.
  4. Dusty message:  We found cool dust at a certain radius from a particular star that contained different ratios of elements than seen on our earth.
  5. Message from the mantle:  We found crystals near a volcano, and studied their melting points and chemical composition.
  6. Older Sierras:  We measured the isotopes of oxygen on leaf fossils found at a certain location in the Sierra foothills.
  7. Cave crystal ball:  There are about 1200 identifiable layers in a stalactite in a particular room of a particular cave in Arizona that average about 100 microns in thickness.

Since this is boring, scientists like to leap off into storytelling land and “explain” how these things got that way.  They look into their zircon crystals and perform divination (see commentaries from 07/26/2008, 01/25/2008).  In their mind’s eye, they see millions of years pass by, mountains emerging, planets colliding, bacteria conspiring, and galaxies evolving.  None of that is based on observational evidence.
    To be really strict, we could require scientists to limit themselves to descriptions of of their perceptions: “I had a sensation of holding a caliper against a stalactite and envisioning a measurement of 100 microns.”  But then how did you know your sensation corresponded to external reality?  Play Descartes: “I doubt, therefore I am.”  We can even outdo Descartes: “Doubting is occurring.”  Further: “I had a dream that someone doubted that doubting was occurring.”  Solipsism.
    This exercise shows that it is far easier to assume support for a theory than to demonstrate it.  David Hume famously challenged the legitimacy of induction and the ability to prove cause and effect.  Nelson Goodman demonstrated that there are infinitely many theories that can explain an observation equally well.  If this seems like academic game-playing, be aware that the greatest minds of the 20th century and before have wrestled with questions like these that bear directly on our ability to connect with external reality.  If we cannot even be sure that our sensations connect with observable reality, how can we claim they connect with “unobservable reality”? (notice the oxymoron from a naturalistic worldview).
    Rather than face these questions, scientists “help themselves” to the assumption that their theories connect with reality.  The successes of science in giving us cell phones and landing rovers on Mars seems to support the belief that science produces reliable knowledge of nature, assuming, of course, that we can define science in some sensible way.  Notice that this is pragmatic reasoning, not logic.  Things could work for other reasons than that they are based on true perceptions of reality.  Egyptians built the pyramids without modern science.  And there are good reasons to believe that humans are incapable of understanding reality.  Quantum mechanics seems to show that at a very fundamental level, matter and energy are counterintuitive.  We use Q.M. because it works; not because we understand it.  Some evolutionists have proposed “evolutionary epistemology” – the idea that if we had not evolved to connect with reality in some reliable ways, we would not have survived.  The argument could just as well be made, however, that evolution to survive (e.g., eat, have sex, fight) has no necessary connection to an understanding of reality – especially to unobservables like galaxy evolution, black holes, quarks, deep time, and the interpretation of climate proxy signatures in stalactites.
    The word science also stands for way too much.  The kind of science that has brought us cell phones and Mars rovers is actually quite limited to experimental work that can be tested in real time.  You don’t need to appeal to millions of years to wire a computer chip.  You don’t need to envision dust disks forming into planets in order to get a parachute to open in the Martian atmosphere.  All the practical benefits of science that have changed our lives have very tenuous connections, if any, to the theoretical speculations in the stories listed above.  Are we to respect the scientists involved in the stories, with all their wild speculations, just because they call themselves scientists?  or just because they work for scientific societies?  Arguably not.  They are fallible human beings like the rest of us.  The successes of science in the 18th through 20th centuries attracted a lot of groupies wanting to cash in.  Like barnacles on the hull of a ship, they tag along for the ride, serving their own selfish needs while doing nothing to propel the ship to the land of knowledge.
    For more on the limits of science and the human elements involved, see the 10/21/2008 entry, especially the last half of the commentary.  For more on the aspirations and pretensions of explanation in science, see 01/13/2010, 12/04/2009, 10/26/2009, 10/05/2009, 04/21/2009, 06/03/2008, or search on “scientific explanation” in the search bar.

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Categories: Astronomy, Cosmology, Education

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