Logical Fallacies 7: The Snap-Shot Fallacy and Affirming the Antecedent

Video here:
http://www.youtube.com/watch?v=TCdm86PgVJY&feature=watch_response

This time, I’ll be discussing two very closely related fallacies; not similar, mind you, but related.  Consider first the common tactic of both creationists and holocaust-deniers.

            “Show me one piece of evidence that the holocaust actually happened.”

            “Show me one piece of evidence that evolution happens.”

            The problem here is that one piece of evidence is not enough to demonstrate anything.  Consider, what single piece of evidence demonstrates that gravity exists or that the Revolutionary War happened?  This is called the snapshot fallacy.  The existence of any scientific phenomenon, the occurrence of any historical event, is established by a convergence of evidence.  Of course, I must now explain.

            What if we already know that, if A is true, then B will turn orange?  What can we do with this knowledge?  How can we use it?

            Well, if at some point we are in a position to observe A but not B, and we see that A is true, we can predict that, if at some point B is observed, it will probably be orange.  But what if B is observable and A is not?  If we are able to observe B and we see that it is orange, can we conclude from this that A is true?  Unfortunately, no.  This is another logical fallacy known sometimes as affirming the antecedent, other times as affirming the consequent.  The logical problem with this particular fallacy is that it gets the premises and the conclusions in the wrong order.  The scientific problem is that it fails to account for the possibility of an extraneous cause.  Maybe B is orange because of some other factor we don’t yet know about or simply overlooked.

            A being true makes B orange but B being orange does not establish that A is true.  By the same token, A not being true does not prevent B from being orange, but if A being true establishes that B is orange, then B not being orange demonstrates that A is not true.

            What is called for here is an act of inductive reasoning instead of deductive.  The difference is that deductive reasoning concerns itself with validity.  Either the supported propositions (a.k.a. conclusions) follow from the supporting propositions (a.k.a. premises), or they don’t.  Either the deductive argument is valid or it isn’t.

            First inductive premise: Most lawyers are conservative.

            Second inductive premise: Such-and-so is a lawyer.

            Inductive conclusion: Such-and-so is most likely conservative.

            The difference here is that the conclusion might be changed in the event of the discovery of additional inductive premises.

            Third inductive premise: Most lawyers associated with the ACLU are liberal.

            Fourth inductive premise: Such-and-so is associated with the ACLU.

            Modified conclusion: Such-and-so is probably liberal.

            Do you see how that works?

            Any historical event or scientific phenomenon is an inductive conclusion.  It’s established on the basis of a currently available body of evidence which is always subject to expansion.  So from the outset, a much longer list of testing criteria must be reasoned out.

            “If A is true, B will turn orange, C will turn backwards, D will invert, E will turn inside-out, F will turn into G and H will disappear.”  Now, we’re ready to test the firmness of this possibility.  Now, if at some point, we’re in a position to observe B and we see that, indeed, it is orange, then this suggests that A is true.  So then we take steps to examine the status of C, and if we find that, indeed, it is backwards, this strengthens the suggestion that A is true, making it more likely.

            Then we check D, and if we find that it is indeed upside-down, then further investigations show us that E is inside out, F and H are no longer visible but G is where before it wasn’t, then A is established as overwhelmingly likely to be true.  The odds at this point that A is otherwise are so small that the act of fixating on them becomes unreasonable.

            So how do we know that the Revolutionary War happened?  Well for one thing, we have volumes of first-hand records from a litany of different sources chronicling it, indeed examining it, battle by battle.  For another, we have hundreds of letters written by soldiers fighting in that war sent to friends and family the details of which place them precisely where troop manifests and duty rosters say they should be.  For yet another, we have those troop manifests and duty rosters.  The only reasonable explanation is that this war did happen.

            Now one could allege that all this evidence is just a forgery, but such widespread collusion would require the most meticulous, precise cooperation among hundreds of thousands of people.  For all of them to go along with it, continuously, for the years of effort required would require a means to keep them all motivated, resolute, and focused to that end.  Any misstep would leave evidence.  Every misstep would leave corroborating, converging evidence.  And the more people who are in on a secret, the harder it is to keep.  So this particular explanation really is neither reasonable, nor tenable.

            Now how do we know that gravity exists?  Can we observe it?  No.  But we can observe and study (and eventually predict) its effects.  We can predict that, if I let go of this pen right now, it will fall.  But more than that, we can predict how far it will fall, about how long it will take to reach the floor, and what speed it will reach.  We can even predict the conversion of kinetic energy into acoustic energy (in other words, the sound it will make) on impact.  We are able to do all of this because of how much we understand about this force, so yet again, denying this force’s existence is really not reasonable.

            Now how do we know that the Holocaust took place?  Well few people in the world are as meticulous at keeping records as the Germans, and as a result, one piece of evidence is Germany’s own census records.  The Jewish demographic is more than six million lower after the second World War than before the rise of the Third Reich.  Now this is not information from just one report.  This is a comparison between reports adding up information from hundreds of other reports from all across Germany.  The Jewish part of the German populace decreased by more than six million in that time.  If they didn’t die in the Holocaust, where did they go?

            Figure into this the abundant anti-Semitic sentiment which pervaded all parts of Europe at the time, the documented rise in anti-Semitic hate-crime, the hate-speech saturating the private correspondence between Hitler, Himmler, Goebbels, Eichmann and hundreds of other Nazi officers and officials, the reconnaissance photos from allied planes flying over the camps showing masses of people being driven from one building to the next, the records, including the execution records from those camps, the remaining memorial museums of the gas chambers and ovens used, the documentation after VE day of all the gas chambers with their walls stained blue coinciding with the use of Zyklon B gas, the footage of the mass graves, the countless allied soldiers involved in the liberation of the concentration camps including General Eisenhower himself testifying to the mass graves, starvation and squalor therein, and the numerous Nazi officers on trial at Nuremberg consistently denying that the Holocaust was wrong, but never actually denying that it happened, and the only wide-sweeping, unifying, all-inclusive explanation of all of this is that the Holocaust did indeed happen.  No other explanation accomplishes this without relying on a long list of warrantless assumptions.

            Now before I continue to the next example, one holocaust-denial observation is that one of the gas chambers (though I don’t recall which) has a door which does not lock, and so this would seem to raise doubts about whether it could have been used as a gas chamber.  Indeed, this would raise serious doubts if the Holocaust were just last month or last year.  But no.  It was more than six decades ago, and after VE day, this particular gas chamber was converted into a memorial museum.  As a result, this odd detail is an anomaly which calls for an explanation, but one is available.

            Anyone in this museum’s staff will be glad to explain this.  You see, this museum has been in operation for a few decades, and so its various doors have been in use all that time, being opened and closed anywhere from a few dozen, to a few hundred times per day.  As a result, this one in particular has worn out and been replaced a few times.  This door which does not lock is not the original.

            Another common holocaust-denial observation is that a brick taken from one gas chamber and tested at a chemistry laboratory showed no signs of Zyklon B gas.  But consider, under what circumstances would one be in a position to remove a brick from a gas chamber?  The chamber in question was reduced to rubble decades before this sample was removed, exposing the inner walls of the chamber to the elements.  This has left ample time for wind, snow, melting snow, and rain to wash away all Zyklon B residue.

            “The door doesn’t lock, therefore this room could not have been used as a gas chamber,” and “The sample shows no trace of Zyklon B gas, therefore it could not have been used,” are both examples of the snap-shot fallacy, in that each attempts to establish a wide-sweeping, far-reaching conclusion on grossly inadequate grounds.  These are each curious observations the like of which call for explanations, but perfectly reasonable, perfectly adequate explanations are available that stop far short of necessitating throwing out the Holocaust or establishing a conspiracy-theory in its place.

            Now observe that, while each of these observations is explained with relative ease, most people don’t happen to have these explanations.  Does this rule out their existence?  Hardly.

            We know about the Holocaust through a convergence of evidence.  If the Holocaust is one big fraud, then that is likewise a historical event, the support of which requires its own convergence of evidence; a convergence the denier will not provide.

            And now, how do we know that Evolution takes place?  Well first, we need to clarify what evolution is.  A 150-year-long sustained propaganda campaign has ensured that this is the most misunderstood concept in the world.  So first, let us clarify.  What do we mean, what are we referring to when we talk about evolution?

            There is to be found on Youtube a video called “The Evolution of Dance.”  What does the title indicate about the content of the video?  It indicates that the video is about how dance has changed over time.  Change over time is what we’re talking about here.  “Evolution” in the general sense of the word means “change over time.”  We began using this term within the life sciences because it became apparent to us that life changes over time.

            Observe that you are different from your parents who are different from their parents.  There is a resemblance of course, and it is closer in some cases than in others, but there is, nonetheless, a difference.  A certain, average amount of change happens from one generation to the next.  For this illustration, let’s call that amount of change “x.”  In one generation, x amount of change happens on average, which means that, on average, in two generations, 2x will occur, and in 100 generations, 100x.  In 5 million generations, 5 million x will occur.  As the passage of time continues, the difference across the generations becomes so great that it is no longer practical to regard the organisms at opposite ends of the span in question as the same species.

            Ah, but we’re not just talking about change over time here.  We’re talking about descent with modification as a result of mutation and natural selection.  What would corroborate this?  That is, if this is the “A” being true in this particular example, what would constitute B turning orange, C turning backwards, D inverting, and so on.

            Consider spiders for a moment.  They’re cannibals.  That is, the vast majority of the time, whenever two spiders cross paths, they fight, and the one who wins the fight kills and eats the one that loses it.  Usually, that is the larger of the two.  Now I say “the majority of the time” because sometimes when they meet, they’re the same species but different genders, and it happens to be mating season, and therefore this instinct is dormant, superseded by the mating instinct.  Under these circumstances, copulation takes place, and then the normal instincts reassert themselves.  The two fight and the winner kills and eats the loser.  The winner under these circumstances is usually the female because she has the advantage of size.

            Now what if the male had the advantage of size?  Well then he would probably be the victor and would kill and eat the female he just inseminated which would mean no eggs and no reproduction.  Thus, in any given spider species, varieties in which the female is larger are able to reproduce while varieties in which the male is larger are not.  I give you natural selection.  This is the observable trend in every spider species we have ever checked for it.

            Now observe that I called them different species; not just varieties of the same species.  What kind of difference designates a change in species and what was merely a change in variety was a problem Darwin and his colleagues used to grapple with quite a bit.  The general rule of thumb today is that, if two organisms are so different that they are unable to produce viable offspring, it’s only reasonable at this point to call them different species.  It’s my understanding that some biologists opine that this point, the point at which they should be recognized as different species happens sooner than this, but the overwhelming majority are agreed that, by this point, speciation has definitely occurred.

            Kirk Cameron observes quite astutely that huskies, schnauzers, poodles, great danes, greyhounds and chihuahuas are all different “kinds” of dogs, but they’re all still dogs.  That’s true, in the same way that human beings, marmosets, field mice, elephants, kangaroos, seals, whales and walruses are all different “kinds” of mammals, but they’re all still mammals.  But when’s the last time someone successfully cross-bread an elephant and a koala?  It can’t be done because they’re two different species.  Now when’s the last time someone successfully cross-bread a pekingese and a basset hound?  This can’t be done either, for the same reason.

            These are each domesticated canines descended from wild canines.  Maybe they’re descended from wild canine species which still exist or perhaps they only share common ancestry with currently-existing wild canines, but in either case, here we have the transition from what Cameron himself admits is common ancestry to a state of reproductive incompatibility.  This is observed speciation.  B is orange.

            Then there are transitional forms.  Some fall under the purview of biology while most belong to paleontology, but they exist.  Whales, dolphins, and porpoises are three different examples of cetaceans each of which has anywhere from a few to dozens of different species, which are distinctly different and reproductively incompatible, but each has a number of things in common.

            First, each spends its entire life water bound yet depends on lungs for respiration instead of gills.  Second, each has skeletons composed of bone instead of cartilage, making them many times sturdier than necessary for oceanic living.  Third, each has finger-bones, toe-bones, and hip-bones, but no fingers, toes, or hips.

            None of this makes any sense at all unless these animals are each descended from land animals by way of descent with modification.  Thus, C is backwards, D is upside down and E is inside-out.

            Now consider the hippopotamus.  Its clumsy form on land does much better in the buoyancy provided by water where one useful instrument upon which it relies is echolocation.  You know; the sort of thing cetaceans rely on.  In terms of evolutionary principles, these two facts about the hippopotamus suggest common ancestry with whales, dolphins, and porpoises.  F has turned into G and H has disappeared.

            And now, think about this: the first uncovered transitional fossil was named Archaeopteryx Lithographica.  Some creationists insist it was completely a bird.  But then why did it have teeth?  Others insist it was completely a reptile.  Then why did it have feathers?  Why would it have traits of both phyla which are otherwise completely unique to these phyla unless it was a transitional form between the two?  Why, unless I has frozen?

            Now what about application?  You know that flu shot you get every year?  To make it, scientists begin by examining the samples of existing flu strains and drawing on established evolutionary principles to predict the three mutations most likely to arise.  The vaccine which results is drawn up as a defense against them.  Now granted, it doesn’t work every single time, but it does work the vast majority of the time, and if evolution were not true, it would almost never work.

            J has grown an extra appendage.  Evolution is a fact established on the basis of a logically-inductive convergence of evidence as firm as that of any scientific principle or historical event.

            Someone, no doubt, is going to point out that none of this is incompatible with the “God did it” explanation or the “An undefined designer of some kind did it” explanation.  That’s true, except for one key problem.  “God did it” and “An undefined designer of some kind did it” are not explanations.  Calling either of these “explanations” is a misnomer.  Scientific explanations are attempts to answer the question, “By what process does this happen?”  Explanations are attempts to describe the process, not the being, responsible for an observed phenomenon.  If a god or an undefined designer of some kind just did something, just made something, then how?  What processes did this designer use?  If something is an intelligent design, then how did the being in question design it?  Did he, she, or it use a drawing board?  If so, then where did the drawing board come from?  Did he, she, or it make that as well?  If so, then how?

            Now, someone, no doubt, is going to respond by saying that we can’t possibly ever hope to understand how God does something.  Well maybe not.  But we can at least try to figure out what processes are responsible for observed phenomena, and our efforts to that end are usually to the benefit of humanity.  This pursuit is the whole objective of science.

            “A designer of some kind” and “evolution” are answers to different questions.